(The Master is watching the Doctor on his scanner.)
MASTER: Bwahahahahahaha! You are doomed Doctor. Doomed! You are piloting your Tardis into a deadly trap and even you will not suspect until it's too late. Bwahahahahahaha!
DOCTOR [OC]: You know, if you're going to spy on me you really should turn the speaker off.
MASTER: My dear Doctor, after our many centuries of conflict I wished you to know that your certain death is now certain! Bwahahahahahaha!
(He turns the scanner off.)
MASTER: But even you will not suspect that your destruction awaits you on Planet Zaston Four.
DOCTOR [OC]: You only turned the picture off, I'm afraid. I can still hear you.
MASTER: I know that. Of course I know that. Curse you!
DOCTOR [OC]: I wanted to talk to you anyway. I have some news that even my arch enemy needs to hear. Meet me on the Planet Terserus in two hours, relative time. And do try not to be late.
MASTER: Mock me while you may, Doctor. My revenge will be all the sweeter. And it will be a deadly vengeance. It will be the deadly vengeance of deadly revenge! Bwahahahahahaha!

[Terserus Castle]

(Atop a bleak mountain. The Tardis materialises and a young woman steps out, followed by the Doctor. Say hi to Julia Sawalha and Rowan Atkinson.)
EMMA: Where are we, Doctor?
DOCTOR: The Planet Terserus, once home to the Terserons, the most kindly and peace loving race I've ever encountered. And yet one of the most shunned and abhorred species of all history.
EMMA: Why?
DOCTOR: They could communicate only by precisely modulated gastric emission.
EMMA: Oh no. Planet of the bottom-burps? So what happened to them?
DOCTOR: They discovered fire.
EMMA: Oh.
(Two energy balls push them against a wall.)
MASTER: Bwahahahahahaha! No doubt because no one has set foot on this planet for a hundred years, you thought you had escaped my traps of death. But you forget, Doctor, I too have a Tardis. When you told me to meet you at Castle Terserus, I simply travelled back in time a hundred years and I bribed the architect. Say hello to the spikes of doom!
(The wall rotates. The Doctor and Emma reappear seated on a sofa.)
DOCTOR: Say hello to the sofa of reasonable comfort. Naturally I anticipated your journey back in time, and so I travelled slightly further back and bribed the architect first.
MASTER: Or so you think! Naturally I anticipated your travelling back in time, so I travelled back to an even further point. And I bribed the architect first.
(The Master aims his laser pointer at the ceiling, and a large slab of masonry falls on them. The Doctor and Emma walk out of a door in the side.)
DOCTOR: Well, naturally I anticipated your journey back in time to an even earlier point
EMMA: Doctor, will you stop showing off. You've got something to tell the Master. Just tell him.
DOCTOR: Very well. I recently calculated that I have saved every planet in the known universe a minimum number of twenty seven times. But you know, I have grown weary of all the evil in the cosmos. All the cruelty, all the suffering, all those endless gravel quarries. And so I have decided to retire, settle down and get married.
MASTER: What?
DOCTOR: Yes. Without even knowing I was looking, I have found a woman to love. A woman more fascinating than all my travels through time and space. A girl more exciting than an escape up a ventilation shaft. A lover more thrilling than an army of cybernetic slugs.
(The Doctor and Emma kiss.)
MASTER: Sadly, Doctor, I am unable to wish you a long and happy marriage, because the moment I am done with this nauseating conversation, I shall travel back in time once more and buy the architect an expensive dinner and suggests that he puts a lever just here
(The Master takes hold of a lever just there.)
MASTER: And a trapdoor leading to the vast and disgusting sewers of Terserus, exactly there!
(Emma moves from where the Master is pointing, but the Doctor pulls her back.)
MASTER: Prepare for five hundred miles of fear and faeces. Goodbye forever, Mister and Mrs Doctor!
(The Master pulls the lever, and plummets through a trapdoor beneath his feet. Splosh!)
DOCTOR: Since you appear to have fallen down a sewer, you won't be able to have dinner with the architect. Although, in fact he's already eaten, because I had dinner with him and suggested he place the trapdoor right here. Phwor. Come along, my dear.
(The doors open. The Master has aged.)
MASTER: Not so fast!
EMMA: How can he be here? He just fell in the sewers. And why's he so much older?
MASTER: Because it's taken me three hundred and twelve years to climb out of those sewers.
DOCTOR: And then naturally you found your Tardis and travelled back in time to the present day, no doubt to wreak one of your terrible revenge things.
MASTER: Yes. But this time I did not come alone.
(Enter a group of Daleks.)
MASTER: After three centuries of having gone through those sewers, only the Daleks would accompany me, because only the Daleks don't have noses.
DALEK: So, Doctor, we meet again.
DOCTOR: Yes. How are things?
MASTER: Observe, Doctor. I am no longer merely a Time Lord. My body has been augmented by superior Dalek technology.
(The Master's right arm has been replaced by a sink plunger.)
EMMA: So what can you do with that then?
MASTER: What?
EMMA: You don't know, do you?
DALEK: Exterminate!
DALEKS: Exterminate! Exterminate!
MASTER: Stop! No! After three hundred and twelve years of climbing through the biggest and most disgusting sewers in the cosmos, after three centuries of wading through those vast steamy lakes, climbing those huge squelchy mountains, after a lifetime of only dung slugs for food and the occasional company on those long, lonely nights. After all that, I'm going to kill the Doctor myself, with my own bare hands! Die Doctor, die!
(The Master lunges forward, the Doctor and Emma step aside and he falls down the trapdoor again.)
DOCTOR: Don't worry, I believe he knows the way out.
(Enter the even older Master, spitting slime.)
MASTER: Six hundred and twenty four years in a sodding sewer.
DOCTOR: This way!
(The Doctor and Emma run off, around the trapdoor.)
MASTER: This way!
DALEKS: Exterminate! Exterminate!
MASTER: After them, you fools! Get them!
(The last Dalek bumps the Master who falls into the sewer yet again. He re-enters with very long silver hair, using a walking frame.)
MASTER: Nine hundred and thirty six years in a sewer. Wait for me! Wait for me!

[Corridors]

EMMA: Doctor, these corridors all look the same.
(The Doctor sees a door.)
DOCTOR: We should be safe in here.
(They open the door.)
DALEKS: Exterminate! Exterminate!

[Dalek ship]

(The Doctor and Emma are tied back to back on a large silver chair.)
EMMA: So, given that exterminating you would be the most sensible thing to do, why do they always change their minds at the last moment?
DOCTOR: I'll explain later.
(The Master enters, looking youthful again. Two golden balls are visible under his jacket, right over where his nipples would be.)
MASTER: Behold! Once again I have been augmented by superior Dalek technology, rejuvenating my physical form and granting me more power over the cosmos.
DOCTOR: And, I notice, breasts.
MASTER: They're not breasts, okay? They're Dalek bumps. They can detect ion charged emissions and operate as aetheric beam locators at a distance of up to twenty thousand light years.
(Emma snorts.)
MASTER: They're also extremely firm.
EMMA: What are you trying to say?
MASTER: Oh, nothing.
DOCTOR: Why are the Daleks helping you? What are you giving them in return?
MASTER: I have granted them secrets of the Zectronic Energy Beam.
DOCTOR: Oh no, you fool. With the Zectronic Energy Beam the Daleks will be able to conquer the entire universe within minutes.
EMMA: With just a beam? How?
DOCTOR: I'll explain later.
DALEK: Prepare to operate the Zectronic Beam in five Dalek minutes.
MASTER: I obey.
(The Master moves away to a console.)
DOCTOR: You may conquer the universe but you'll have to share it with the beard and the bosoms over there.
DALEK: (sotto) The Master will be exterminated when he has served his purpose.
DOCTOR: (sotto to Emma) Psst. If the Master knew that the Daleks intend to kill him he might help us. EMMA: How are you going to tell him without the Daleks hearing? They'll exterminate you on the spot if you say anything. I think we've really had it this time.
DOCTOR: Don't cancel our wedding yet, my darling. There's just one thing you've forgotten.
EMMA: What?
DOCTOR: Daleks don't have noses.
EMMA: Scraping the barrel a bit there, aren't you?
DOCTOR: Think my dear. Back on Terserus, the Master and I both bribed the castle architect. Not only do I speak perfect Terseran, but so does he.
EMMA: You mean?
DOCTOR: Yes. I can communicate with the Master by carefully controlled breaking of wind.
EMMA: (to another Dalek) Could I be tied to a different chair?
DALEK 2: Silence.
EMMA: Why do you have chairs on a Dalek spaceship anyway?
DALEK: We will explain later.
(The Doctor concentrates and the Master sniffs.)
MASTER: Danger?
(The Doctor nods.)
MASTER: You are facing certain doob. Certain doob?
EMMA: Try not to clench.
MASTER: The Daleks are planning to exterminate you as soon as you twiddley heepy jeepy
EMMA: Sorry, that was me.
DALEK: Cease this communication!
DALEK 2: You have betrayed the Daleks!
DALEKS: Exterminate! Exterminate!
(The Daleks fire at the Master, who ducks, so the beams hit the Zectronic Beam Controller. They also shoot the Doctor.)
MASTER: You fools! This Zectronic Beam Controller will now not only explode, it will implode. We're doomed.
DALEK: Repair the Zectronic Beam!
MASTER: It is beyond my ability. Only the Doctor can do it.
EMMA: Help him, he's dying. Yes, my darling?
MASTER: He, er, he says I love you.
EMMA: Oh Doctor. You've killed him!
MASTER: I think not my child. This is only his ninth body. He has many, many more. Behold, the miracle of the Time Lord!
(The Doctor regenerates into Richard E Grant.)
DOCTOR: Oh, sorry about that. I just though I'd slip into something more comfortable. Result? Cute, sexy and lick-the-mirror handsome.
(He licks the mirror.)
DOCTOR: I remember you, don't I?
MASTER: And you still fear me, Doctor?
DOCTOR: You're the camp one.
MASTER: I'm not camp.
DOCTOR: Oh, yeah? Nice tits.
MASTER: Bumps.
DOCTOR: I remember you lot, of course. And, er, you're my fiancée?
EMMA: You remember me then?
DOCTOR: How could I possibly forget the only time travelling companion I've ever had?
EMMA: You've had lots of companions.
DOCTOR: The only time travelling companion I've had. 
EMMA: Oh, right.
DOCTOR: It's still me in here, Emma. These old hearts are still yours. Can you still love me in my new body?
EMMA: Actually I don't think I'll have to much of a problem with that. Back to the Tardis?
(The Tardis is nearby.)
DALEK: The Zectronic Beam Controller is going to explode.
DALEK 2: Help us, Doctor, and you're life will be spared.
DOCTOR: What better way to end my career than saving you metal gits? Pop into the Tardis, get a bottle of good champagne. When you get out we'll celebrate the beginning of our new life together.
EMMA: Great.
(Emma goes into the Tardis while the Doctor goes to the Zectronic Beam Controller and starts fiddling.)
DOCTOR: I think in my new body I'm going to be particularly good at rewiring.
(He goes around the back of the device and it goes bang, flash. Jim Broadbent steps out.)
DOCTOR: Oh, bugger.
(Emma enters.)
EMMA: Doctor?
DOCTOR: Ah. You're my fiancée aren't you? Oh, dear. Seem to be a bit shy of girls now. All the problems of changing personas. So unpredictable.
EMMA: Doctor, look at me.
DOCTOR: In a minute. Oh dear, another girl. 
MASTER: I'm not a girl, Doctor, I've told you before. These are Dalek bumps. They can locate aetheric beam emissions and everything.
EMMA: So, er, you don't want to try again, do you?
DOCTOR: Probably not a bad idea, actually. Shouldn't be too much of a problem. Actually, I think the problem's probably located in this area.
(The Doctor disappears down a short corridor. Bang! Flash! Enter Hugh Grant.)
EMMA: Result!
DOCTOR: Oh dear, now look at that. I've gone and used up three bodies in just under a minute, and all because I forgot to unplug first. That really was terribly silly of me. Sorry about that, my dear. Bit unfortunate.
EMMA: Oh, Doctor. 
DOCTOR: Oh, assistant.
(Before they can lip-lock, the Doctor is zapped in the back. There are energy beams bouncing all around the room. He collapses by the door to the Tardis.)
EMMA: Doctor!
DOCTOR: Residual energy. I'm a stupid ass, I should have realised.
DALEK: The Doctor has saved the Daleks. His life will be spared.
MASTER: No, his life is already lost. That was a discharge of pure Zectronic Energy. Even a Time Lord cannot survive its terrible power.
EMMA: But he can just change again, can't you, Doctor?
DOCTOR: I'm afraid not, my dear. Zectronic Energy too powerful. It has destroyed my ability to regenerate. I'm afraid this is the end. Look after the universe for me. I've put a lot of work into it.
EMMA: But how can we look after it without you?
DOCTOR: I'll explain
EMMA: Doctor, listen to me. You can't die, you're too, You're too nice, too brave, too kind and far, far too silly. You're like Father Christmas, the Wizard of Oz, Scooby Doo. And I love you very much. And we all need you, and you simply cannot die.
MASTER: He was the best and bravest of all my foes. From this day forward I will renounce evil and follow the path of goodness to honour my fallen foe.
DALEK: The Doctor saved the Daleks. The Daleks too will honour their mortal enemy.
EMMA: He was never cruel and never cowardly, and it'll never be safe to be scared again.
(The Master leads Emma away. Behind them, the Doctor regenerates.)
MASTER: It's impossible! Beyond all known laws of the universe.
EMMA: Maybe even the universe can't bear to be without the Doctor.
(Joanna Lumley stands up.)
DOCTOR: Emma, look. I've got aetheric beam locators.
EMMA: No, Doctor. I'm afraid those are actual breasts.
DOCTOR: Are you sure? I think I can see the on switch.
EMMA: No, Doctor, we have to face facts. You've come back to life and this time you're a woman.
DOCTOR: Really? I've always wanted to get my hands on one of these.
EMMA: Unfortunately, I haven't. 
DOCTOR: You're mother's going to get a bit of a surprise at the wedding, isn't she? Do you think we'll both wear white?
EMMA: I'm afraid, Doctor, and I'm not sure if this sentence has ever been used so completely accurately before but, you're just not the man I fell in love with.
DOCTOR: Well, never mind. We can still rattle around the universe, fighting monsters and saving planets. What could be more fun? My best friend by my side, my trusty old Tardis and, of course, my sonic screwdriver.
(She switches it on, and it begins to vibrate.)
DOCTOR: Ooo look, it's got three settings.
EMMA: Doctor, stop that!
(Emma grabs the screwdriver and throws it across the room.)
MASTER: Doctor, I have to say you are rather gorgeous.
DOCTOR: I'm not bad, am I? And come to think of it, you're a great deal more attractive than I remember.
MASTER: Why, thank you.
DOCTOR: Tell me, why do they call you the Master?
MASTER: I'll explain later. Bwahahahahahaha!
(The Master and the Doctor walk away, arms round each other's waists.)