The Lazarus Experiment was the sixth episode of the third series of Doctor Who. It saw regular writer Mark Gatiss take on an acting role and marked the Doctor's acceptance of Martha as his regular companion. It included a large number of "Harold Saxon" references and saw Francine Jones' first involvement with his aides.


To have an adventure investigating the unusual, there's no time like the present!

After travelling backwards, forwards and backwards again in time, Martha Jones has returned home. However, before the Tenth Doctor can bid farewell to her, he hears Professor Richard Lazarus announcing that he'll "change what it means to be human." What could this mean? And could it lead to something far more dangerous than a simple scientific failure?


The TARDIS materialises in Martha's flat. The Tenth Doctor tells her that they had agreed — one trip and home. It is about twelve hours after they left, something the Doctor failed to do with Rose in his previous life. Martha's phone rings, but she does not pick it up; it is her mother Francine, saying that her sister Tish is on the news. Martha turns the television on and, alongside Tish, an elderly man, Professor Richard Lazarus, announces that tonight he "will change what it means to be human." Though looking thoroughly perturbed at what was just said, the Doctor says goodbye to Martha and, oblivious to her upset, steps into the TARDIS. It dematerialises, but quickly rematerialises. The Doctor reemerges, saying, "No, I'm sorry, did he say he was going to change what it means to be human?". Evidently, he cannot resist this.

At Lazarus Laboratories, Professor Lazarus and Lady Thaw discuss the need for the experiment to work, with Thaw mentioning that Mr Saxon is funding their research. Tish comes in, asking if Lazarus would like to check over the guest list again. He stops her and tries flirting by asking what kind of perfume she wears; she tells him "soap" and quickly excuses herself.

The Doctor and Martha attend Professor Lazarus' black-tie reception that evening, where the Doctor complains about how something bad always happens when he wears black tie. Martha remarks that it is simply him, not the outfit, and that she thinks it makes him look like James Bond in a way, flattering him. There, they meet Martha's mother and her brother Leo. Martha introduces the Doctor to her family; Francine is suspicious of him. Tish also meets the Doctor, wondering how he got in as he's not on the guest list. Martha explains Tish works in the PR department before Tish corrects her; she's head of the PR department, having put together the party herself. The Doctor inquires what kind of experiment Lazarus is going to perform with the large capsule in the room, being labelled a "science geek" by using big words. He questions Martha as to what it means, seeming rather pleased with the answer.

The lights of the room dim and a spotlight focuses on Lazarus, who announces he is to perform a "miracle", which will outstrip all other human accomplishments in the field of science, even the splitting of the atom. Declaring that they will wake tomorrow to a world changed forever, the elderly professor steps into the manipulator's capsule. Technicians flip the switch and the capsule flares to life with a blinding flash of light; four manipulator arms circle the capsule at breakneck speed while manipulating threads o light up and down it. As the machine builds in intensity, an alarm blares and the consoles smoke and spark. The Doctor notices that the system is overloading and jumps in to avert disaster. Lady Thaw demands that someone stop him, but the Doctor declares that if the machine explodes it will take the entire building with it. He pulls the plug, and the machine comes to a stop. Martha rushes forward at the Doctor's urging and yanks the door open.

The Lazarus Experiment 160

The rejuvenated Lazarus emerges.

The crowd advance slowly on the capsule. Out of the steam steps a young blond man; Lazarus. He smiles as he touches his newly rejuvenated face and declares that he is 76 years old "And I am reborn!". Despite the momentary crisis, his experiment appears to have been a success — but the Doctor is certain there are dangers the professor has overlooked. He talks to Lazarus about having experience with a similar process, taking notice that he's experiencing hunger from a depletion of energy; the Doctor tells him that he couldn't have thought of all the variables that could have happened. Lazarus scoffs at the Doctor's warnings, so the Doctor and Martha sneak off to conduct their own tests, taking a DNA sample from Martha's hand, which Lazarus has just kissed. Their test shows Lazarus's DNA suddenly spike and change; something which should be impossible. The Doctor reels off a lot of complicated scientific lingo but simplifies it for Martha's benefit. The esteemed professor hacked his own DNA and instructed it to rejuvenate. However, "something's been activated; something that won't let him stabilise, something that's trying to change him."

Meanwhile, Lazarus speaks with Lady Thaw in his office on the top floor, telling a story about his childhood during World War II. Thaw expresses her desire to be the next to be rejuvenated so they can continue their partnership both personally and professionally. He rejects her, joking that not only did he learn cruelty from her, she has a gift for it. As she threatens to complain to Mr Saxon, Lazarus begins spasming. To Thaw's horror, Lazarus mutates into something horrendous. A scorpion-like tail raises itself and lunges at her.

Downstairs, Francine asks Tish and Leo whether Martha has ever mentioned the Doctor to them before. She worries there is "something going on", but Leo tries calming her down by saying Martha's found someone to be with. Lazarus returns to the reception, back to being himself and wearing a different suit, and invites Tish upstairs with him. Tish, now willing to return his advances, follows without argument.

The Doctor and Martha emerge in Lazarus' office, searching for him. As Martha suggests trying back at the reception, her voice trails off as she spots a bony leg sticking out from behind the desk. Investigating, they find the shriveled husk of Lady Thaw; the Doctor says she had all the life energy drained to supply energy to the processes caused by Lazarus' fluctuating DNA. Worried he will kill again, they go back downstairs, only to learn that he has gone off with Tish. They rush off, the Doctor accidentally spilling a drink on Francine. Another man replaces her drink, and darkly warns that Martha should be more careful in choosing her friends.

Lazarus takes Tish to the roof, where he talks about nearby Southwark Cathedral and quotes T.S. Eliot, a quote the Doctor completes before they trade barbs; Lazarus believes he has perfected humanity by purging it of mortality, while the Doctor is infuriated at his disregard for the laws of Nature. As they argue, Martha gets Tish away from Lazarus before he transforms. They stand, transfixed in horror, as they behold Lazarus' mutated form; resembling a huge, skeletal scorpion, a facsimile of Lazarus' face stares out of the monstrosity. They flee indoors and the Doctor seals the door behind him. As they wait for the lift, Lazarus' attempts to smash the door down triggers a security lockdown; the lights dim, the lifts stop and the exits seal themselves, much to the confusion and slight panic of the guests. Rushing downstairs, the Doctor gives Martha the sonic screwdriver to unlock the doors, and warns everyone at the reception to get out. One woman refuses to believe this, stating jokingly that the biggest danger is choking on an olive. Suddenly, all heads turn as a great shattering of glass is heard and Lazarus appears on a balcony overlooking the reception area, roaring loudly. Now more inclined to listen, the assembled guests scream and scatter as Lazarus wreaks havoc, striking Leo in the head with a table. As Martha finally gets the doors open and the partygoers scramble down the stairs, Lazarus advances on the olive woman and deploys his stinger; the Doctor shouts for him to leave her alone, but too late. Guests still in the room avert their eyes as the woman's withered husk hits the floor and Lazarus turns towards a prone Francine and Leo. The Doctor draws Lazarus away from Francine by taunting him that Nature has gotten her revenge for his defiance. Lazarus chases the Doctor down a corridor. Martha examines Leo, gets everyone out of the building, and goes back inside to help the Doctor despite Francine's protests. Tish guesses that "maybe she loves him". The man who replaced Francine's drink earlier calls the Doctor "dangerous", and whispers in Francine's ear the things he says she "should know" about him.


The Doctor tries to find a way out of Lazarus' machine.

The Doctor turns on the gas in a lab and leaps away from the resulting fireball, but Lazarus survives. Martha hears the explosion and finds the Doctor as she runs toward its source. She returns the sonic screwdriver to the Doctor. They flee together, and end up hiding in the capsule of Lazarus' machine, on the Doctor's hunch that Lazarus is unlikely to destroy his own creation even to get at them. The Doctor starts fiddling about with the wiring inside as the Lazarus creature futilely searches for a way in. Martha, still unsure of where it came from, inquires if it is alien but the Doctor nixes that; for once, the horrible creature trying to kill them is strictly human in origin. Martha reacts with disbelief, as the creature couldn't look any less human, but the Doctor explains that what happened is the machine unlocked something hidden away in Lazarus' genes; an option which evolution rejected for humanity, but the potential for which still lies dormant. Martha likens it to Pandora's Box, but their ruminations are cut short as Lazarus switches the machine on. The Doctor "reverses the polarity" so that the capsule will reflect the energy rather than receive it, which it does explosively. The shockwave blasts the creature away, transforming Lazarus back to human in appearance — and apparently killing him. As they gaze upon the body, Martha and the Doctor reflect on how pitiful he looks, the latter quoting T.S. Eliot: "This is the way the world ends, not with a bang but a whimper."

Outside, as the ambulance carrying Lazarus' body pulls away, Francine slaps the Doctor, and tells him to keep away from Martha.

Suddenly, all turn their heads when they hear a loud crash nearby. The Doctor, Martha and Tish take off and find that the ambulance has gone off the road. Opening up the back doors, they find that Lazarus has killed both paramedics for their energy and escaped. They find him in human form inside Southwark Cathedral, where as a child he took refuge during the London Blitz. The Doctor says he was present during the Blitz, but Lazarus says that he is not old enough to have been there. They argue again about the benefits and curse of longevity. Martha (accompanied by Tish) then lures Lazarus away to the top of the bell tower; the Doctor told her earlier that Lazarus could be defeated if he could just get him up there.
The Lazarus Experiment 848

The Doctor watches Lazarus's death.

As the Lazarus monster chases the Jones sisters at the top of the cathedral, the Doctor pulls out all the stops on the pipe organ, inserts the sonic screwdriver, and plays it at maximum volume, setting up a resonance in the bell above Lazarus that interferes with his sonic-based experiment. Lazarus falls to the cathedral floor below, transforming one last time — back into the elderly man he once was.

Back in Martha's flat, the Doctor offers Martha one more trip, but Martha refuses to go with him on that basis, as a mere passenger being given a treat. The Doctor says, "Okay, then, if that's what you want." She thinks he means to leave her again, but he indicates with a nod that she is welcome to rejoin him on her terms, and admits she was "never really just a passenger". They leave together in the TARDIS. As it disappears, Martha's phone rings; it is Francine. She warns Martha about "who this Doctor really is", saying, "This information comes from Harold Saxon himself. You're not safe!"



General production staff

Script department

Camera and lighting department

Art department

Costume department

Make-up and prosthetics



General post-production staff

Special and visual effects


Not every person who worked on this adventure was credited. The absence of a credit for a position doesn't necessarily mean the job wasn't required. The information above is based solely on observations of the actual end credits of the episodes as broadcast, and does not relay information from IMDB or other sources.

David Bednall was uncredited for his organ performance.


  • The Doctor states that he has to turn the sound "to eleven", a reference to the mockumentary "This is Spinal Tap".
  • The Doctor claims to have been taught how to play the pipe organ by Beethoven.
  • Harold Saxon is mentioned by Dr Lazarus, Lady Thaw, and Francine.

Story notes

  • This is the second time in the revived series when the Doctor jumps from an explosion, first seen in The Unquiet Dead.
  • Gatiss's appearance makes him one of a select few to have both written for and acted in the show, and the first of the revived series to do so. Gatiss' involvement with the Doctor Who franchise dates back to writing for the Virgin New Adventures novel series in the early 1990s, as well as appearing in and writing several independent spin-off video productions. Gatiss also voices "Danny Boy" in Victory of the Daleks (which he also wrote), reprises the role in A Good Man Goes to War, and portrays Gantok in The Wedding of River Song, though he was credited as "Rondo Haxton" for the latter role.
  • As the rejuvenated Lazarus, Mark Gatiss wears a wig he previously wore in an episode of The League of Gentlemen, playing a veterinary surgeon based on Peter Davison's character in All Creatures Great and Small. When the Doctor Who make-up department told him they didn't have time to get a new wig made, he offered to use the League of Gentlemen wig that he had at home. The BBC ended up hiring it from him for a hundred pounds. Gattis recounts the story in great detail on the audio commentary for The Lazarus Experiment.
  • The name "Lazarus" is a reference to the Biblical man who was resurrected from the dead, similar to being given youth back. The comparison is made explicit when he escapes the ambulance and the Doctor says, "Lazarus, back from the dead. Should've known, really."
  • The set piece for the capsule of Lazarus's Genetic Manipulation Device is actually the redecorated descent capsule from The Impossible Planet/The Satan Pit.
  • Lazarus (Mark Gatiss) says he once lived above a butcher's shop as a child. In his role as Hilary Briss in the BBC series The League of Gentlemen, Gatiss is well known for playing a butcher.
  • When Martha introduces the Doctor to Francine, Francine's response is, "Doctor what?"
  • David Tennant and Mark Gatiss had previously appeared together in the Big Finish audio story Sympathy for the Devil.


  • 7.19 million viewers - BARB Final Rating
  • 6.7 million viewers - Overnight
  • 0.98 million viewers - BBC3 Repeat

Filming locations

Production errors

If you'd like to talk about narrative problems with this story — like plot holes and things that seem to contradict other stories — please go to this episode's discontinuity discussion.


Home video releases


Series 3 Volume 2 DVD Cover

  • This episode was released with Daleks in Manhattan, Evolution of the Daleks and 42 on the Series 3 Volume 2 DVD.
  • It is also part of the series 3 DVD box set.
  • A deleted scene establishes that the Doctor once helped Thomas Jefferson draft the US Declaration of Independence, and he specifically takes credit for the reference to "the pursuit of happiness". The Doctor finds the first draft of the document in his tuxedo pocket.

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