Director: Charles Palmer (III)
Show Stars: David Tennant (The 10th Doctor (Season 2 - )), Freema Agyeman (Martha Jones (Season 3 - ))
Recurring Role: Adjoa Andoh (Francine Jones), Paul Kasey (Judoon Captain)
Guest Stars: Reggie Yates (Leo Jones) , Trevor Laird (Clive Jones) , Gugu Mbatha-Raw (Tish Jones) , Roy Marsden (Mr. Stoker) , Anne Reid (Florence) , Nicholas Briggs (Judoon Voices) , Vineeta Rishi (Julia Swales) , Ben Righton (Morganstern) , Kimmi Richards (Annalise)
Production Code: NCFT081P
Martha Jones is heading for work when her sister, Tish, her brother, Leo, her mother, Francine, and then her father, Clive, call to get her to sort out their issues concerning her brother’s upcoming birthday party. She’s interrupted when the Doctor, a man she’s never met, greets her on the street and gives her his tie. She then arrives at the hospital where she attends as a medical student. A black-suited motorcycle-helmed figure bumps into her. Later, on her rounds, she attends to a woman with a salt deficiency, Miss Finnegan, then discovers the Doctor, who is admitted as a patient by the name of John Smith and claims not to recognise her from earlier. Martha is puzzled when she tries to listen to the Doctor’s heartbeat, then receives a brief static electrical charge – others comment that there has been a lot of static earlier that day.
Martha then calls her sister, who is outside the hospital and tells her that a thunderstorm has surrounded the hospital. They notice that the rain is going upwards. There’s a surge of electricity and everyone in the hospital is thrown back and forth. It’s now dark outside and when they look out they realise they’re on the Moon.
Doctors and patients in the hospital panic but Martha realises that the hospital must be surrounded by a force field maintaining the air. The Doctor is pleased at her deductive abilities and gets her to take him out on the veranda where there’s still air. Martha is impressed by the view and doesn’t want to leave, again impressing the Doctor. The Doctor determines where the force field is and they figure the air will eventually run out. They’re interrupted when three alien ships arrive overhead and land nearby. The new arrivals emerge and the Doctor recognises them as the Judoon, rhino-like humanoids.
Meanwhile, Miss Finnegan meets with the head Doctor, Dr. Stoker, taking two of the black-suited men in with her. She reveals that she needs to feed on the salt in his body and inserts a straw into his neck to drink his blood.
The Judoon come through the force field and enter the hospital, causing a huge amount of panic. They quickly assimilate the language and start identifying staff and patients as humans, marking them with a cross on the hand. The Doctor explains that they’ve isolated the hospital and brought it to the Moon, and is concerned since he isn’t human. The Judoon move through the hospital, killing one man who opposes them.
The Doctor is checking up on the hospital records and reveals that he noticed plasma coils at the hospital and decided to investigate. The Doctor reveals that if the Judoon find the hospital staff and patients guilty of harbouring a fugitive, they’ll kill everyone. He then determines that the invaders have wiped the computer records by accident. Martha goes to get Dr. Stoker and finds Finnegan feeding on him. The two bikers come after her as she runs into the Doctor and they head downstairs, only to be caught in-between the bikers and the Judoon. They take another corridor and take refuge in an examination room. The Doctor rigs the x-ray device to generate beams at 5,000% their normal strength, and when Martha activates it, he focuses it on the biker, killing him. The Doctor the discharges the radiation by focusing it into his left shoe, and reveals the biker was a Slab, a basic slave form. Martha reveals Finnegan is the alien and the Doctor realises that she is an internal shape shifter, assimilating blood.
The Judoon catch up with Finnegan, who mimics Stoker’s biology using his blood, enabling her to pass their test. The Doctor and Martha try to stay ahead of the remaining Slab, but are scanned by the Judoon who realise the Doctor isn’t human. Another chase ensues and the Doctor hides on a floor they’ve already checked. People are starting to show signs of oxygen deprivation as the Doctor and Martha make their way to Stoker’s office. They find his blood-drained corpse there and the Doctor wonders why Finnegan is still there. The Doctor kisses Martha then leaves her there to create a distraction while he runs for the MRI chamber, where he finds Finnegan working the equipment. The Doctor feigns confusion and Finnegan has her Slab grab him while she continues to prepare the equipment.
Martha tries to stop the Judoon, who pick up the non-human Doctor’s trace on her lips. Meanwhile, the Doctor probes Finnegan for information and discovers she plans to enhance the MRI and destroy everyone within 250,000 miles, including everyone on the side of the Earth facing the Moon. She will then take the Judoon ships and make her escape. The Doctor mentions that the Judoon are increasing their scans, and Finnegan realises she has to consume more blood to pass the test. She takes out her straw, and starts feeding on the Doctor’s blood.
The Judoon give Martha compensation for searching her without sufficient reason, then continue their search and find Finnegan and the seemingly-dead Doctor. The Judoon determine that the Doctor is deceased, and Martha tries to get to him. When she can’t, she accuses Finnegan and asserts she’s not human. Realising Finnegan drank the Doctor’s blood, Martha scans her and picks up the Doctor’s trace. The Judoon confirm that she is a plasmavore who killed an alien princess. Finnegan confesses and sends her Slab to stop them, but he fails. Finnegan puts the MRI into overload before the Judoon disintegrate her. The Judoon confirm that the magnetic pulse is increasing and evacuate because the situation is outside their jurisdiction.
Martha administers CPR to the Doctor, allowing for the fact he has two hearts. With oxygen running low, she administers a rescue-breath and revives the Doctor before collapsing. The Doctor shuts down the MRI device then carries Martha to the window and sees the Judoon reverse the teleport procedure. On Earth, the gathered crowds look on as the hospital returns and emergency workers move in to revive the dying patients. Martha talks to her sister, but sees the Doctor leave in the TARDIS.
Later, at the Jones birthday party, fighting breaks out and, after everyone goes their separate ways, Martha spots the Doctor across the street in an alleyway. She goes in after him and finds him standing by the TARDIS. The Doctor invites her on a trip and when she doesn’t believe him, he dematerialises briefly then returns. He comes out and shows her the tie from when they met earlier. The Doctor invites her in and she discovers it’s larger on the inside than the outside. The Doctor admits he was travelling recently with someone else, Rose, but asserts he’d rather be on his own. He states that he is just rewarding her with one trip since she helped him. Martha claims she isn’t interested, despite his kiss. The Doctor kicks things into gear, takes off the hand brake, and they dematerialise for a bumpy ride.