Original subtitles

It really does say "supercop".

Have you got anywhere with that cypher, anywhere at all?

So since you've been here, you've solved four murders

and not a single letter of that thing?

I need the source code.

Right, well, work out what and where it is, then!

Oh, no, that computer woman's here.

She almost caught me this morning.

Caught you doing what?

Chief Constable Ziegler has been accessing a lot of files lately

from your computer, even on the days he's not been there.

What do you think you're playing at?

Who is this?

Yes?

Mr Durose?

Mr Durose?

I've told you, it's locked from the inside.

Here.

Haven't you got somewhere to be?

Yes, sorry, miss.

Out.

Out, now!

Out! Everybody out!

Go, go. Get out! Oh, my God!

What's happening? What's going on?

Freya, what is it?

You didn't go back to bed!

We all agreed to go back to bed.

Are you not even going to ask us what we found out?

You've found something out?

James's phone...

..has been cracked.

Really? It was fine when I had it.

Hmm?

What? No, crack... Hacked.

Someone's tampered with the software,

set it so that you can't withhold numbers any more.

That asterisk before the number that called last night,

that's what that means. It was supposed to be withheld.

They didn't know we could see it.

That's weird, right? I did some googling.

Networks can do it, but users shouldn't be able to.

It's hardly James's area of expertise.

Holly? She does seem good at that sort of thing.

Well, maybe she's been helping Dad all along.

She doesn't seem to like me - or, rather, him.

Possibly a bit of both.

You need to talk to her, today, alone.

Alone? You need to get on with it because we've hit a dead end here.

Yeah, we... We tried calling it back, but it doesn't take incoming.

It's his old partner, Matt Neville.

It has to be.

If it is him, then he's ex-directory.

The area code is for Manchester, but you can buy area codes.

He could be anywhere. Good.

Good? If you knew the address, you'd insist on going to see him.

And I'd tell you that that was too dangerous, and you'd tell me,

"OK, I won't go then," but then you'd just go and see him anyway.

Don't you have a detective to impersonate?

Yes.

And talk to Holly.

Alone!

Mum? Mm-hm? Erm...

If I told you I might know a way to get an ex-directory address,

would you be willing to not make a big thing about how I know?

Doors closing.

Ah, there you are, guv.

Great timing. Hmm?

Let's go. Go where? Back to school.

Well, my school certainly never looked like this.

Mine did.

We even had a clock-tower just like that one.

Morning, guvs.

The body's already gone.

Saw it, though. Not pretty.

I'm going to say it had been here a couple of days at least.

The caretaker broke in with a drill. Door was locked from the inside.

Looks like a suicide.

There's even a note.

Handwritten? Typed.

So the deceased was the headmaster?

Yes, sir. Ian Durose.

Been here 20 years.

Promoted from Head of English in 2015.

Head of English, eh?

Standards must have plummeted.

Two double negatives, no apostrophes.

And how did he do the deed, jump off the desk?

Leaving no footprints, no shoe marks,

not disturbing a single thing?

I mean, that's the straightest pile of papers I've ever seen.

I've seen straighter.

But, yes, if you're alluding to the fact this scene appears staged,

I would agree.

This wasn't suicide.

This was murder.

Yes!

Knew it. Sorry, sirs. It's just...

It's just that's what I was saying earlier. Wasn't it?

Yeah. I'm glad I didn't take the bet now. The...

I... I mean...

I'm glad that there wasn't a bet, because why would there be a bet?

We don't bet.

We don't bet. Mm-mm.

We don't bet. Sir.

I-if it was a murder, though, how did the killer get out?

I mean, the windows are painted shut and the door

was locked from inside... No, it wasn't.

Oh, it definitely was, sir.

No, it can't have been.

Don't really think it's in question, boss, sorry.

It was locked from inside. The key's still in it.

Well, seeing as you're not here to collect your winnings,

Detective Sergeant, what do you have for us?

Right, yes, sorry.

Erm, we've shut down this building and the pupils have been moved

to the sports-hall. I think they're sending them home.

And who's in charge?

There's a deputy head, I presume?

Ms Chordwell.

She's a bit shaken up. She found the body.

Ah, guv?

How do you know how to do all this?

You did say you wouldn't ask that.

That was before I found out it was on the Dark Web.

I mean, isn't that where you buy drugs and hire hit men?

Possibly. I don't know.

I do know you can get ex-directory addresses on here, though.

Henry! What?

OK, a friend - not me - used it to send a fleet of taxis

to our geography teacher's house - one an hour, all night long.

Mmm, that is quite funny.

Thank you! I mean...

..I will... I will pass that on.

Oh, I've got it. Really?

Yeah. It's an address in Wales.

It's registered to a woman, not a man.

Gillian Botley.

Do you know her?

No.

Are you sure?

Of course I'm sure.

You're not going to go are you, Mum?

Only I do think Uncle John's right on this one.

Dad's letter says, "Trust no-one"...

Oh, Henry, do give over. ..and if you don't even know

who this woman is... You're starting to sound like him.

I'm not going anywhere. I do have a day-job, you know?

Go and have a shower.

Thanks, Henry!

Don't ever go on the Dark Web ever again.

Murder?

The postmortem will either confirm or deny this,

but for expediency, we need to work on the assumption that it was.

But the door was locked from the inside.

Yes. Which is really annoying. Have you any idea how that happened?

What? Perhaps a better starting question would be,

when was the last time you saw Mr Durose?

Just before I left. I saw him heading to the office.

He often worked late. I do too.

But it was a Friday after a long week and I just wanted to get home.

And where is that, home?

I have a cottage here on-site.

And so does Mr Durose.

But you were here, ah, basically, at the school all weekend?

And you live alone?

No, I live with my...

Well, fiance now, actually.

Though I don't have a ring yet.

Mr Bishop.

He's the sportsmaster here.

He was away over the weekend,

house-sitting for his parents up in the Highlands.

Very nice.

Erm, you didn't go with him?

No, we had a tiff.

But it doesn't matter now.

And you didn't see anybody else on that Friday evening?

One of the housemasters.

He left late. I saw him out the window heading to a car.

But he's not all there sometimes.

He used to be our maths teacher, but he doesn't actually teach any more.

Probably fell asleep in the office. Wouldn't be the first time.

Mr Todd?

What, you know him?

Ah, Mr Todd.

Oh. Hello.

Morning.

Sorry to intrude. No, you're not intruding. I'm...

I'm just doing the morning puzzles.

Which ones? Oh, I...

Well, my name's DI Russell Carter and this is DCI...

Well, I actually believe you two may, erm, know each other.

Oh, yes, it's Taylor, sir.

I attended St Edwards. Taylor. The Taylor boys?

Oh, the Taylor boys?

Oh, yes!

I remember the Taylor boys!

Yes. Ah, Jacob and... Joshua.

Ah, no, sir. James and John.

That's right, yeah. Which are you?

James.

Master James, of course.

Yes. You were the nervous, awkward one.

Ah, no. That was... That was my brother.

Really? Yes, really.

Sorry, would you mind if I just, ah... No.

And, well, what is it I can do for you gentlemen?

Well, obviously we're here to investigate the death of Mr Durose.

Oh, yeah, of course. Of course you are.

I'm so sorry.

I've been having a senior-moment, I'm afraid, yes.

Mr Durose was a...

He was a good, kind man.

It's thrown me for quite the loop.

Whatever I can do to help you, just say.

I understand you may have been working late Friday evening?

Erm, it's possible...

Friday, you say?

What day is it today?

Erm, it's Monday, sir.

Ah, yes... Ah, thank you, Taylor.

Oh, I recall now. Yes, I did leave early that day. Erm...

I'm rather embarrassed to say I may have had a little doze.

Do you not think you should wear your glasses when reading?

Hmm? My glasses?

Erm...

Ah... Oh.

Oh.

Well, that all seems in order.

Ms Chordwell believes she saw you leaving at around 7pm.

I wouldn't dispute that.

Do you recall whether you saw anybody else,

or indeed anything out of the ordinary?

Or a vehicle you hadn't seen before... No, no.

Nothing like that at all, I'm sorry.

Do you know, I'm not actually sure that I'd spoken to

our headmaster that day...

..or even seen him!

Oh! No. Ah, yes...

I did see him, just before final bell.

I didn't talk to him, though.

I'm afraid he was having a rather heated exchange

with our sportsmaster.

Mr Bishop?

That's, ah, Ms Chordwell's fiance, right?

Fiance?

She mentioned they were engaged.

No. No, no, no, no. I don't think so.

Erm...

What was this heated exchange about, sir?

I'm afraid I don't know - I'm not one for eavesdropping.

And I avoid Mr Bishop like the proverbial plague.

The man's a bully, and I hate bullies!

And I certainly don't like them as teachers.

So... young James Taylor, eh?

Ho, ho, ho!

And how's your brother?

I was always very fond of him.

He was very fond of you too, sir.

I imagine he has a family by now, does he?

A family?

Yes, he has... family.

Ah!

You OK, guv?

Must have been weird bumping into your old teacher like that.

He'd... He'd got nearly half those puzzle solutions wrong.

So?

So he was the most brilliant man I've ever known.

What happened?

Well, nothing happened, guv.

He just got 30 years older, that's all.

Taylor...

Nice shorts. Your mum get you them, did she?

Well, yes.

Well, what you stood here for? Aren't you meant to be in PE?

Go on, then. Don't want to be late, do you?

Everything in order, gentlemen?

Yes, sir!

Ah, Master Taylor!

Is it John or James? John, I believe. Yes.

Well, excellent timing.

I need a hand sorting some papers.

I've got PE, sir.

Well, I'll write you a chit.

And, you two, shut that door.

There's a terrible draught in here.

Come on, put that over there. That's it.

Sir?

Are you police?

Detectives, yes.

What, both of you?

Huh!

You carry on. I won't be a moment.

I was in at 7.00 packing all that up.

Supposed to be taking the rugby team on a two-day out-bounder.

Really? All my PE teacher ever did was make us run around a field.

You need to train up willpower as well as just muscle.

48 hours roughing it with scant provisions is worth 100 laps

around the track.

Obviously I had to cancel it now.

Obviously.

Your fiance mentioned you were away for the weekend.

She is your fiance, right, Ms Chordwell?

There seems to be a bit of confusion over that point.

We got engaged this weekend.

I thought you were in Scotland.

They do have phones in Scotland.

You got engaged over the phone?

Over video, if you must know.

But I don't see what that's got to do with anything.

It hasn't. We're just clarifying.

What we did want to talk to you about is your relationship

with Mr Durose. We understand you had some sort of argument with him

on Friday afternoon?

What? That wasn't an argument - who told you that?

Oh, right. Sure, yeah. The nutty professor.

I wouldn't listen to much of what he says.

He's on the verge of being let go as it is.

Why would the school want to lose Mr Todd?

Have you met him?

Doesn't even teach any more, hasn't done for two years now.

They gave him some pity job as housemaster, and now he just

sits around earning 60 grand a year for doing nothing.

Even a place like this is feeling the pinch these days.

Durose was planning on letting him go. Everybody knew it.

Including him? Of course.

You didn't tell us what the argument was about.

Upton! Get out here.

Isaac Upton is the captain of our rugby team.

Last week, he was caught smoking marijuana on the school premises.

That's illegal! It was just half a joint.

That doesn't make it half legal.

Yeah, well, I don't care whether it's legal or not.

What I care about is a rugby player inhaling smoke into his lungs.

Mr Upton here isn't the most academic of boys.

He is, however, on course for a sports scholarship

right here in Cambridge.

Is that what you were arguing about? I wasn't arguing.

I was... pointing out that any suspension or disciplinary action

on his record will affect the rest of his life.

And did Mr Durose agree?

He said he'd need to ask advice from the board.

I don't know whether he ever did.

Right.

Well, under the circumstances, and just to draw a line underneath it,

we need to ask whether you have an alibi for Friday evening.

Ah, yeah. I was at my girlfriend's.

Sasha Sparks, head girl.

Right, go on. Finish unpacking, then clear off.

He's a moron, but he's a moron that's won us

two trophies this year.

Now, anything else?

Er, yes.

Do you have an alibi?

I was several hundred miles away.

That's more of a statement than an alibi.

No, it's just the truth.

But I'm sure one of the locals would've seen me at some point

if you really need an alibi. Yes, please.

It might be helpful.

I'll have a think.

Did you see the state of that one?

So what are you thinking, guv?

I'm thinking he did it.

I sense you're not a fan of PE teachers.

Two things can be true at once.

I'm telling you, sir, it was locked from the inside.

The key was still in it and multiple witnesses saw it being drilled open.

But it can't have been!

So we have statements from the entire staff, 30 in total.

We have around 200 more coming from the students.

We need them all.

A headteacher is the type of victim that has almost

an endless pool of suspects.

That being said, we have a few prime candidates

that have found their way to the top -

starting with the heir to the throne, someone with

everything to gain, which presumably includes a giant leap in salary.

She comes up in quite a few of the statements.

She actually seems well liked as a person, but there's

definitely a split amongst staff when it comes to her politics.

Mr Durose was pretty old-school - pardon the pun.

Ms Chordwell is vocally much more progressive.

She'd apparently tried to push quite a few policy changes -

genderless uniforms, that sort of thing -

but they were all rejected.

We have a student, Isaac Upton - rugby hero with a bright future

that was on the verge of a crash and burn.

He was caught smoking weed, which could potentially scupper

his scholarship.

Mr Durose was going to write a letter to the board

asking for advice on how to proceed.

But we're not sure whether he did that or not.

Contents of his bin included healthy and unhealthy snacks,

several discarded letters, though they were to rather than from him,

and they were just about general everyday school stuff.

Er, there's his computer, of course, which is presumably

where everything is typed and saved. But Holly's on that.

Holly's here? Well, downstairs in her office, yes.

I-i-is she coming up later?

I don't know, guv. If she finds something, I guess.

Then there's the sportsmaster, who is recently engaged to Ms Chordwell.

Apparently he spent the weekend alone in the middle of nowhere.

Oh, he came back to us with an alibi.

Passed a couple of hikers.

Didn't know any of them. All untraceable.

What about his motive?

Well, take your pick from the first two, Sergeant -

either manipulating his fiance into a position of power

or ensuring his sports star can continue to be his sports star.

And then there's, er, Mr Todd -

ex-maths teacher, current housemaster,

and apparently, according to rumours, not long for employment.

No alibi for him either.

Everyone seems to think that he was on borrowed time.

Yeah, a couple went to pains to point out how he never married,

never had children.

Nothing but an empty house to come home to every night.

This job was his whole life.

See, it's a strong motive, but...

This is a complicated, risky and seemingly impossible crime.

And having spoken to him for five minutes, there's...

There's no way he could have done it.

Could it be a trick lock? Are those a thing?

"Gillian Botley"? Do you know who that is?

Never heard of her. Are you sure?

Yes, I'm sure. Why does everybody keep asking me that?

It's just another dead end, fake address, fake name.

Well, I mean, we don't actually know if...

I'm a little bit disappointed with you, John.

You couldn't find five minutes to talk to Holly.

But she never came upstairs. Why didn't you go downstairs?

I can't go down there. I'm... I'm not allowed.

Says who?

I think she mentioned it once.

But you're a DCI, she's a civilian. You can go wherever you like.

I'm sure she'll come upstairs tomorrow.

Talking of tomorrow, I've got an assignment -

a big wedding, too big to turn down. I have to stay over. It's in Leeds.

Why would someone from Leeds hire a photographer from Cambridge?

Because I did her last wedding -

she liked the photos, just not the groom.

I'm sure you can cope for one day without me.

Can make a lads' night out of it.

A lads' night? Well, what exactly does that entail?

I don't know? I've never been a "lad". Neither have I.

Yeah, and I'm pretty borderline, to be fair.

Goodness me! Do you want me to cancel it?

Is that what you want? No, of course not. Yes, please.

Er, no, of course not. You must go.

Right, then.

Oh, morning, boss.

Postmortem confirms strangulation, not hanging.

Your instincts were right. Ahem. Yeah, yeah, yours too.

Oh, these... 200 student statements.

Feels like we've been doing homework ourselves.

DI Carter's already back at the school, wants you to join him.

Yes, but the Chief Superintendent would like to talk to you first.

She's in your office with Holly.

Holly? What are they talking about?

I don't know, Sir... The case?

The case. Yes, that... That would make sense.

Well, I'd... I'd better go in there, then.

Off I go.

Morning, DCI Taylor. Have you seen this?

Headmaster of a posh, expensive school...

They're loving this, and with a couple of hundred pupils,

all on Instagram, there was no way of keeping it quiet.

So all eyes on us again, I'm afraid.

Do I need to give you my customary speech?

Erm... No... Ma'am.

Good, because as you can imagine,

I've had Chief Constable Ziegler in my ear all morning.

I've sent DI Carter straight back there.

Plus, we have some new information for you.

I got into Durose's computer.

There was a letter about Isaac Upton, unfinished.

There was another letter too, completed but unsent,

regarding a Mr Bishop

and rumours of inappropriate conduct with a female student.

What sort of inappropriate conduct?

Well, if you can't guess that, DCI Taylor,

maybe you should go back to school yourself.

I'm just saying. Right...

Erm... Well, was that all you wanted to talk to me about?

Is that not enough? Oh, no, no, of course it is.

How are you, anyway? What? Yeah, I'm fine.

Right, good.

Are you two just staying here, then, in... In... In my office?

Is that a problem? No.

Morning. You spoken to the Super?

Lessons all cancelled, and students were told to stay home,

but apparently rugby practice is far too important to miss.

You heard about the letters, I take it? Yeah.

We haven't spoken to him yet,

because this bloody thing's been going since I got here.

Yes! Yes! Run! Run!

Yes!

Upton, that's my lad.

Great work... OK.

If there was a letter about me, it's the first I've heard of it.

I actually can't believe Mr Durose would have listened

to that sort of rubbish. You'd heard the rumours, though?

I look younger than I am and I take care of myself.

Girls get crushes, they fantasise, they make stuff up,

they tell their friends. Whoever this one is,

she isn't the first and she won't be the last.

Well, I presume it was Sasha Sparks?

I saw you touch her.

I'm sorry, Detective. Can you say that again, please,

just so I can remember it for my lawyer?

Solicitor. What? Erm... Sorry. Guv, you saw him touch her?

Well, yes, didn't you? Just... Just now, on the playing field.

I patted her on the back!

Her boyfriend had just won the game! What's wrong with you?!

I don't think we need to get confrontational

here. I'm getting confrontational?!

It's your little friend here that's all but accusing me of... Mr Bishop!

Let me make this very, very clear for you.

I don't listen to rumours, my fiance doesn't listen to rumours,

and if you had any idea how this sort of place works,

neither would you.

And I follow the first and only rule of sport -

I never cheat!

Hello? Hi, Mrs Taylor?

Speaking.

I'm just calling from the school, Henry didn't appear to be

at registration this morning, so we just want to check everything's OK.

Yes, er... Tummy bug, sorry, I forgot to call.

Oh, that's fine, we just need to check...

What do you think you're doing? What do you think YOU'RE doing?

I might suck at geography, but I'm pretty sure Leeds is North.

You did know the name Botley, didn't you?

Matt's wife's maiden name.

Dad and I were at their wedding. Matt Neville...

I knew it!

OK. Pull over, let me get in the front.

Whoa, no, no, no, no! You're not coming with me.

No? What are you going to do?

Leave me on the side of the road or drive three hours back to Cambridge?

Side of the road is pretty tempting... You wouldn't.

Oh! Hi, erm...

Oh... Oh, my goodness, I'm so sorry. I just spoken with Mr Bishop...

I'd heard the rumour too, but it's not uncommon,

especially for someone like him.

Someone who looks young and keeps himself in shape?

Is that how he put it? Well, I'm not surprised.

No, more like someone who still thinks

and acts like he's one of the sixth-formers himself.

It makes him over-friendly with them.

That's always been the problem.

Is that what your tiff was about?

No, no, not really. Well, not at first.

I was actually the one that caught Isaac with the joint.

That was what it was about mostly.

He didn't think I should report it, I knew I had to. Quite right.

And unfortunately that was also the night he left for Scotland,

meaning we didn't actually part on good terms,

so the tiff continued all weekend.

I wrote him essays, just poured it all out,

every insecure thought I'd ever had, about him and me.

Got a lot of "OKs" and "Right", "Go on", and not much else.

He finally rang on Sunday, about one o'clock.

I'd gone for a walk and came back to a long video message,

mostly rambling apologies, and then, suddenly, out of the blue,

ending with a proposal.

As if he'd only just realised it himself,

he added, "I really mean that."

And... And he did.

I could see it.

And that sentence meant more than the proposal to me.

Thank you. I don't suppose you brought anything, a toothbrush?

Yeah, I did not think that far ahead. No. No, no.

Oh, would you mind, darling? Chop chop.

Hello?

Hello. Slight change of plan.

Henry had a couple of study days, so I've roped him in to helping me.

So, you mean I'll be...

..home alone? Yes. You've lived alone for 30 years, John.

Yes, but in my home, not yours. Where are you? Er... A hotel.

Wedding's in the morning. Is... Is Henry with you now?

Mm-hm... Henry? Oh, erm... Hello?

You take care of your mum, OK?

Yeah, I will.

Thank you.

Goodbye.

He knows.

Course he doesn't. Ah!

Guv? Everything OK? Should we head back to the station?

Er, I'll meet you back there.

I... I need to see a man about a door.

Oh, do, er...

Have a seat, Taylor.

Now, in case you haven't figured it out...

..I don't really have any work for you.

But I presume you don't really want to go to PE

or walk past those boys again, eh?

Bullies are insecure.

That's why they bully - always remember that.

Ah, yes, what do you make of that?

I don't know, sir. What is it?

Well, it's a puzzle, isn't it? Obviously.

Why don't you have a crack at solving it?

Is it for a test, Sir?

No, no, no, it's just for me, really. I like making them.

I find the process quietens a busy mind.

Might be something you should try sometime.

You strike me as a boy with an especially over-busy mind yourself.

So... You just made this up, Sir?

Yes.

It's not hard.

Well, hopefully, the puzzle is, but making it isn't. You...

You merely start with a solution, work backwards

and then layer in a few false paths

to confuse the less laterally-minded amongst us.

Is it a three, Sir? Reflected?

I had a feeling about you, Taylor.

Ah! Taylor, how are you?

Oh, I'm sorry, did we have a meeting scheduled?

Erm, no, Sir, I was just, erm...

Erm, I actually wanted to ask you a question, Sir.

Erm... I'm a bit stuck on a...

Well, on a puzzle, I suppose,

and I know that was always your forte, so...?

Oh, please, I'm all ears.

A man was killed inside a locked room, his body was discovered

three days later with the room still locked, from the inside.

There's only one way in or out.

How did the killer leave again and re-lock the door behind them?

They didn't. But they did.

Yeah, on the contrary, the one thing we know for certain

is they didn't, because that would be impossible, wouldn't it?

But... Oh, do stop butting, Taylor. Honestly, boy, you know this.

If a solution is impossible, then it's impossible by design,

thereby making it...?

A false path. Uh-huh.

One that was deliberately layered in. Mmm.

So... So, what's the real solution?

Well, you tell me. It's your puzzle.

You do understand that I'm talking about the murder of Mr Durose, Sir?

Oh, I do apologise. I thought it was just...

Ah, yes, Mr Durose...

Of course, that was a terrible thing.

Off, are you, Detective? Yes.

Can I ask you something?

What was it that made you decide to pursue a career with the police?

It just sort of happened. Did it?

I've heard there's always two types that join up, Alphas and Betas -

Alphas because it's a natural fit, and Betas because authority over

others is the only way that they can make up for their shortcomings.

I thought that was PE teachers!

It's very awkward for you, isn't it,

that door being locked from the inside?

Makes me wonder if justice will ever be served.

Oh, I promise you it will.

I knew it! It was Mr Bishop. He did it, he's the killer.

Oh, yes!

That is two cans of Coke and a Freddo you now owe me.

No, no, no, that is not fair! You knew I was going to choose him.

That's why you said it first, that's...

Yeah, yeah, sorry, can we all just slow down for a minute?

He practically confessed! You have a confession?

I mean, not technically, no.

But he was very sarcastic. Well, can you prove it?

That he was sarcastic?

No, Detective Chief Inspector, that he did it! No.

And it seems impossible,

but he did.

Hello?

How are you? Enjoying having the house to yourself?

No, I hate it. Thought you liked your own company.

Don't know what gave you that idea.

The last three decades.

John, are you OK? No, I'm not OK.

I didn't manage to talk to Holly,

I know who killed the headmaster but I can't prove it,

I've just spilled tea all over my puzzle,

and I can't stop thinking about my old maths teacher.

Erm... That last one's a bit weird. He was my mentor, Lucy.

My... My inspiration...

The only person who ever actually made sense. He WAS me.

Still is. He's the me I'm going to become in another 20 years -

a sad, lonely old man with nothing in his life, but an empty house...

Hey, that's not true, John. You'll meet someone... No, I won't.

That was my brother's path, not mine.

I never even cared about it,

because as far as I was concerned, I'd always have my mind.

It didn't occurred to me that could vanish too.

It has for him.

You're not alone, you'll never be alone.

Listen, this is what we're going to do.

As soon as James get's back, we're going to...

..build you a granny flat, right on the side of the house.

I never wanted you not to be in my life.

You were the one who always...

John? Are you there? John?

Yes, hello, sorry, I... I was looking at a banana peel.

What? I've got to go.

A granny flat?

Oh, great. You.

Don't tell me you've solved it? Some of it.

What... What are you doing here?

It's called overtime.

Holly, wait.

I...

About that thing... the other day, with the log-ins and... stuff.

Why did you cover for me? Are we really going to do this, are we?

Are we really going to keep pretending

like nothing happened between us?

The Christmas party?

You kissed me, remember? Not the other way round.

Oh, right, so you're just going to deny it, are you?

No.

I can't. No, you can't.

Are you waiting for something? What are we even doing here?

Right, perfect, OK, then.

Er... Hello.

I... I don't know if any of you know this,

but Mr Todd here, as well as being a terrific teacher,

is also one the greatest puzzle setters this country has ever seen.

I asked his advice on this little "locked room puzzle" of ours.

He said the solution was impossible.

He was correct.

By trying to answer the question of how the killer left an office

that was locked from the inside, we were being led down

a false path that had been deliberately layered in.

The killer never actually left the office at all.

What? That didn't make sense. I think that was probably the idea.

I mean, who needs an alibi for a murder that wasn't possible?

It was a shame that camping trip you were going on

was cancelled, Mr Bishop,

though in fairness, you had just returned from one of your own -

three whole days, with scant provisions,

equipped with nothing but the iron willpower needed to

bed down on a hard floor next to the corpse of a man you murdered.

Is this a joke?

Interesting. How did he get out again, Taylor?

Oh, quite easily, Sir, the...

The body was clearly visible from the door.

It doesn't take much intellect to work out

what the reaction would be, once it was opened.

Oof!

Out! Out now! Out! Everybody out!

Go!

What's happening? What's going on?

I threw out a banana peel last night.

Two hours later, it was already browning.

There was an apple core in the headmaster's bin.

It had barely turned its shade.

It could only have been eaten that morning, inside that locked room.

Breakfast, was it?

Bit absent-minded of you to throw it in the bin,

when you'd obviously gone to all the effort to bag up

and remove everything else you'd been surviving on.

But given how poorly you faked the suicide, I...

I can't say I'm surprised. Well, take a DNA swab if you like,

but I can tell you now that I ate that apple

on Friday, in this office, in a meeting with Mr Durose.

And as for its colour...

Well, you're a science teacher - go on, tell him.

Oh... Erm...

It depends on many factors, like room temperature and...

Exactly. So you even got this apple core any more?

How brown is it now?

You call that evidence?

Oh, I doubt it would even make it to trial

if that was all we had, but fortunately we can do a lot better.

I'm afraid to say you were rather integral to his plan, Ms Chordwell.

I don't know if the accusations against him were true,

though one doesn't tend to kill over rumours,

but I do know that with his partner in charge of the school,

matters certainly wouldn't have been taken further.

But that part had started to go wrong, hadn't it, Mr Bishop?

The row you orchestrated

to give yourself the excuse to disappear for the weekend

had been instrumented a tad too aggressively,

leading to you having to spend the whole weekend desperately

messaging back and forth to a woman who was beginning to ask herself

if you even had a future together,

resulting in your impromptu and...

..romantically questionable video proposal.

Constable Evans...?

Constable Evans?

Oh, yes. Oh, sorry...

Ms Chordwell was kind enough to share this with us.

I know... I know that I can, I can sometimes be...

But it doesn't mean that...

Christ, Freya, I want to spend the rest of my life with you.

I want to marry you.

I mean, will you? Will you marry me?

God, I actually really mean that...

I'm sure you never expected something so personal

to be shared with anyone other than your fiance.

And you also knew that she wouldn't have been able to hear

what we just did.

I presume we all heard it?

Heard what?

The bells, of course.

We had a clock tower at my old school.

I always hated it.

I think you're going to spend the rest of your life hating yours, too.

Huh!

Argh! Oof!

Bradly Bishop, I'm arresting you on suspicion of murder.

You do not have to say anything, but it

may harm your defence... I do hate bullies.

Lucy? What are you doing here?

You called James two nights ago.

That wasn't James, was it? Where is he? I don't...

I don't know, but if he knew you were here, then...

What's going on?

No.

No, no, no, no! We've got to go! We have to leave!

We don't have to leave. How do you know she wasn't followed?!

Followed by who? Is this all connected to the Sinclair case?

The one that you and James were working, the blogger?

Matt, please? We don't know who she's been talking to.

You what? My husband's no longer on the force,

and you need to leave, now, before you get us all...

Get us all what? Mummy! Hey!

Hello! Everything's OK, everything's fine.

How do you fancy a trip away? You, me and Daddy?

A holiday, yeah?

Matthew! A second... Matt, come on.

Lucy, I'm sorry. Please, come on. Just... I'm sorry, I'm sorry...

Matt!

Ah, Taylor, do come in!

It's... It's OK, Sir, I'm... I'm not stopping, I...

I just wanted to say goodbye. Ah. And to thank you, for your help.

Oh, not at all! Glad I could be of assistance.

Was I of assistance, then?

It's all you've ever been, Sir. Ah.

Taylor, do you mind if I ask you a question?

Why are you pretending to be your brother?

Do you think I don't know my students?

You're not James, you're John.

So, what's it all about? This ruse you're engaged in, hmm?

It's... complicated, Sir.

But it's all for a noble reason. Ah, that's what I hoped.

Sir, I've been doing this for a while now.

I go to work every day and I'm surrounded by detectives,

sergeants, superintendents, trained sleuths...

..yet none of them have worked out that I'm not who I say I am...

..but you did.

I can't tell you how relieved I am

to know that you're just as brilliant now as you ever were.

I always had a good feeling about you, Taylor.

Thank you, Sir.

Not going to talk to me for the whole journey, no?

You shouldn't have gone there alone.

Yes, well, I did, and as I said, the place was abandoned.

They've moved on, if, indeed, they'd even been there in the first place.

Don't believe you, and neither will Uncle John.

Yes, well, we're not going to tell Uncle John, are we?

Look, Henry, if he thinks either of us put ourselves in danger,

he'll pull the plug on this whole thing.

The place was abandoned.

OK?

Thank you.

See you tomorrow, Sir!

Oh, stop sulking! Hey, you might win the next one.

Stranger things have happened.

Hey. Hello.

Hi, you're up.

Yep. Here I am.

Up. Oh, any news? Did you speak to Holly?

No! I mean, yes, but it... It wasn't what we thought.

What was it, then?

Erm... Nothing.

She just likes clearing log-ins, I think.

That's not possible, that... That doesn't make any sense.

How was the wedding? The what? Yes. Fine.

Yes...

Nothing to report, then?

No.

Very much like yourself, it would seem?

Right.

Right.

Hello?

Lucy Taylor? I'm Holly, I work with your husband.

Holly?

How... Sorry... How...

How did you, erm, get my number?

I can't sit with this any longer. I need to talk to you, in person.

Tonight.

Tonight? I'm not sure that I... It's about James.

I'll text you the address.

Please come.

Your wife has been arrested on suspicion of murder.

You think it was them? Of course it was them!

And whoever they are, they are here now.

For all I know, they're right outside this door...

I do have a strong working theory on how Lucy didn't do it.

I think you should come with me, both of you.

Get away from this place.

No more conspiracies, no more murders.

No more danger.

Is this a dream?