Transit (serial)

Transit is the third story in Season 29. It was written by Ben Aaronovitch, directed by Fraser C. Heston and featured Richard Griffiths as the Doctor, Julia Sawalha as Katie Tollinger and John Banks as Henrick.

This story is notable for being the last story to feature Julia Sawalha as Katie Tollinger as a companion.

Synopsis
It's the ultimate in mass transit systems, a network of interstitial tunnels that bind the planets of the solar system together; Earth to Pluto in forty minutes with a super save non-premium off-peak travelcard. But something is living in the network, chewing its way to the very heart of the system and leaving a trail of death and mutation behind it.

Once again a reluctant Doctor is dragged into human history. Back down amongst the joy boys, free surfers, chess fans, politicians and floozies, where friends are more dangerous than enemies and one man's human being is another's psychotic killing machine. But will Katie survive the adventure?

Part 1
In the year 2109, the Earth's colonies throughout the solar system are connected by the Sol Transit System, or STS, a system of train "tunnels" through the fabric of reality itself. Travel is fast, nearly instantaneous; and the ambitious human race is about to open its first interstellar addition to the system. The first Star Tunnel, or "Stunnel" for short, will go to the colony at Arcturus, 26 light-years away. Something goes drastically wrong, however, when something unknown pushes its way out of the tunnel and into the body of the system itself, vaporizing everyone on the platforms for the opening ceremony.

Lunar University (or "Lunarversity") student Kadiatu Lethbridge-Stewart—a distant descendant of Brigadier Alistair Gordon Lethbridge-Stewart from an illicit relationship in his early military days in Africa—gets briefly involved with a group of special maintenance workers on the Stunnel project, and develops a hasty but passionate relationship with Zak, or Blondie as he prefers to be called, the youngest member of the crew. Related events lead her to be at King's Cross station when the entity from the tunnel passes through, destroying everyone; but she is saved by the sudden appearance of the Eighth Doctor, Katie Tollinger and the TARDIS. The TARDIS itself, with Henrick still inside, is hurled to the end of the line, somewhere in another station. Stuck with few options, the Doctor and Katie fall in with Kadiatu, who connects him to a family friend, a woman named Francine, who is—famously—a completely blind veteran of the war on Mars between the humans and the Ice Warriors some twenty years earlier, and also an accomplished underworld boss. Unknown to the Doctor, Kadiatu knows exactly who he is.

Henrick finds himself in a slum near the last station in the solar system, on Pluto, and falls in with two waitresses, Roberta and Zamina. (By coincidence, Blondie is also from this slum, and is well known to both girls.) Henrick quickly uses the girls, as well as a local gang, to seize power and then spark a riot that sends destruction careening through the slum. Roberta is killed in the fighting, and Henrick escapes. Meanwhile, the Doctor knows a thing or two about Kadiatu, as well—he realises that she has been genetically engineered, probably as a soldier. He discovers her rather complete files on him and learns that she is very close to discovering time travel, a few centuries early for humanity. He considers deleting the files, but decides against it, fearing the repercussions. He also realises—though she didn't tell him—that she is a descendant of his old friend. When she awakens, he helps her solve a minor problem she is dealing with, and in return, recruits her to help him and Katie recover Henrick and put an end to the crisis in the STS.

Blondie's crew, led by a former—and a highly augmented—soldier called Old Sam, begins to search the now-closed system for the source of the problem, using a modified maintenance train they call Fat Mama. They are assaulted by a group of mutated individuals and barely escape with their lives and heavy damage to the train, though one crewmember—Dogface—is critically wounded and whisked off to a hospital. They report into their supervisor, the System's manager, Ming, often called "Ming the Merciless". Meanwhile the Doctor, Katie and Kadiatu make their way to the slum on Pluto, where the fighting has ended and the relief workers have arrived. There they find the TARDIS; it struck the wall of the station with enough force to embed it deeply in the wall, with the door, unfortunately, facing the wrong way. Henrick arrives at the station, and tries to kill the Doctor; it becomes clear that he is possessed by the transit system entity.

Part 2
The Doctor is saved by Old Sam and Blondie; Henrick flees, collecting Zamina as she does, and joins a refugee group headed for Mars. During the fight, Kadiatu discovers—and is disturbed by—her own preternatural fighting skills, which she does not understand; a flashback shows that she herself is not her parents' natural child, but was found by her father on a military mission, organized by Francine. She was genetically engineered by the Imogen corporation as a supersoldier of incalculable ability; however, her father couldn't bring himself to kill the infant warrior, and adopted her instead, vowing to overcome her creation with a good upbringing and psychology. She knows none of this, however.

The Doctor takes Katie, Blondie and Kadiatu to his house in Kent, where the couple's relationship deepens. The Doctor realises that the STS hasn't been invaded by an outside intelligence; rather, because it is structured in the form of a complex neural network, it has evolved its own intelligence. He builds a device to communicate with the system and finds that while he is correct, he only has part of the story. The system, though certainly intelligent, was invaded by a competing intelligence—a virus of sorts—from another dimension, which breached the system where reality was thin along the Stunnel's path. The Doctor decides to help the system expunge the virus. He contacts Ming and her fellow executives and offers to help—and none too soon because something in the system is preparing to open the Stunnel again.

Henrick and Zamina are placed with a family on Mars, but Henrick quickly kills them. She heads out, intending to get to STS control and advance the virus's plan—but she manages to resist the virus's control long enough to send Zamina away with a warning for the Doctor. The Doctor gets the message, and takes Katie and Kadiatu to Mars via the tunnels, finding that Henrick has fled in a vehicle out onto the wilder parts of the surface. He leads them to an abandoned Ice Warrior nest, where he tries to shoot the Doctor; Kadiatu kills him.

Part 3
The Doctor is furious until he realises it's not the real Henrick; it's a mutant made to look and sound like him. He was a decoy.

Waiting to be picked up, Kadiatu compares notes with the Doctor and Katie about her family history, and then reveals something disturbing—she has dreams about an old woman, whom the Doctor identifies as the Pythia of Gallifrey's past, giving a curse against childbirth. Francine arrives in a modified jet and picks them up, but is shot down by an automated system that misinterprets her intentions. She lands safely somehow, though the plane is destroyed. A chance encounter with one of the rescue crew that collects them makes the Doctor realise that he may be far too well known to humans now, and he considers deleting knowledge of himself from human records.

Henrick makes his way to STS control and sets the reactors to overload, pouring power into the Stunnel's grid, preparing to open the gates on both ends. The Doctor, Katie and Kadiatu arrive but find that it's another false Henrick. The Doctor sends the maintenance crew's drones to build a machine to draw power from the TARDIS, and then he and Katie head to the Stunnel station by free surfing the tunnels—that is, travelling them on a board, without a train. Inside the tunnels, the Doctor picks up an unidentified, disembodied hitchhiker, telepathically entering his mind. At the other end, he and Katie find a battle in progress, between the entity's mutants and the human security forces, with Blondie and Old Sam there holding the line as well. Blondie dies in the process, horrifying Kadiatu. Henrick—the real Henrick this time—is there as well. As the Doctor arrives, the gateway opens, and the full entity emerges, possessing Henrick; it seems the version that was already inhabiting him was only an agent of sorts. As it claims no name, the Doctor calls it "Fred". However, before it can act, the machine connected to the TARDIS fires a powerful burst of artron energy through the tunnel, channelled through the Doctor, striking Fred and driving it back into the tunnels and into its own dimension, taking Henrick with it. As the Stunnel starts to collapse, the Doctor follows it in, trying to rescue Henrick; Katie and Kadiatu follow him. During the process of the two crossing the Stunnel, it collapses, and just as they reach the end of it, to save Kadiatu's life, Katie pushes her through, as she herself, falls to her death, into the vacuum of space, suffocating, but sacrificing her life to save Kadiatu.

The Doctor finds himself in a world of subjective reality, malleable to the wills of those inside it. He shapes reality into a form he can navigate and leaves messages for Kadiatu to follow. He also finds that the artron energy—representing the TARDIS itself—takes the form of two cats, one green, one silver. He battles his way through to a confrontation with Fred. Fred admits that it has concealed its true purpose until now; it can't act with impunity in the real world, but here, it has more power; and it saw the potential in the Doctor, and wanted to take him to augment its own power. To that end, it kidnapped Henrick, planning to lure the Doctor here so it could acquire his mind. Kadiatu arrives manifesting as a leopard, and attacks Fred; the Doctor transfers the hitchhiker from his own mind to Henrick's, forcing Fred out, and Kadiatu devours Fred. The hitchhiker then vacates Henrick's mind and takes form—it is the Transit entity, and now, without any opposition, it feels comfortable vacating the system and remaining here in this dimension, where it can reach its full potential. The Doctor, Henrick, and Kadiatu return to reality just as the gateway collapses. Kadiatu informs the Doctor and Henrick about what happened to Katie, both react with horror and sadness.

The crisis is resolved; but before leaving Earth again, the Doctor visits the Stone Mountain data repository on the moon, which contains the sum total of human knowledge. He has deduced that its AI management software has become sentient, and threatens to expose it to humanity—who are paranoid about such things—if it doesn't accommodate him. He persuades it to delete all records of his own existence on Earth, and he personally destroys what hard copies are available; and in return, he gives it pointers on how to live with humanity. It names itself FLORANCE and immediately begins establishing a presence on Earth, before revealing itself. The Doctor returns to the station on Pluto and has the maintenance crew cut the TARDIS free of the wall, and takes a very shaken Henrick with him when he leaves. He sees that Kadiatu gets a job with STS. He offers her a chance to come with him, but she refuses—but warns him that she'll give him a head start, then come after him. Later, she completes her time machine, and then destroys all her research, before setting off after the Doctor—but where her allegiance lies, remains to be seen.

Cast

 * The Doctor - Richard Griffiths
 * Katie Tollinger - Julia Sawalha
 * Henrick - John Banks
 * Kadiatu Lethbridge Stewart - Sharon D. Clarke
 * Francine - Sarah Smith
 * Old Sam - Simon Russel Beal
 * Credit Card - Tommy Flanagan
 * Dog Face - Max Beesley
 * Lambada - Barbara Flynn
 * Blondie - Iain Glen
 * Ming the Merciliss - Patsy Byrne
 * F.L.O.R.A.N.C.E. - Jennifer Saunders

Crew

 * Writer - Ben Aaronovitch
 * Producer - Ian Fraser
 * Script Editor - Ben Aaronovitch
 * Director - Fraser C. Heston
 * Lighting -  Brian Handley
 * Designer - Tony Woolard
 * Visual Effects Designers - Malcom James, Dave Chapman
 * Make-Up Designer - Suzanne Reynolds
 * Casting Director - Anne Henderson
 * Music - Mark Ayres
 * Costume Designer - Ken Trew
 * Edited by - Howard Billingham
 * Vision Mixer - Julie Miller
 * Original Theme Music - Ron Grainer
 * Title Music - Mark Ayres
 * Title Sequence by CAL Video

Memorable Quotes
To be added.

Production History
To be added.

Development

 * This story was initially proposed for Season 25 but was rejected by Andrew Cartmel.
 * During production of Season 29 Ben Aaronovitch developed his script and decided to use it in the current Season.

Production
To be added.

Post-Production
To be added.

Reaction

 * Official BARB ratings: 7.0m for Part One, 7.8m for Part Two and 8.2m for Part Three.

Story Notes

 * This is the final story to feature Katie until Ashes to Ashes, Dust to Dust in Season 36.
 * This is only the third story to kill off a companion. The other two are The Daleks Master Plan which killed off both Katarina and Sara and Earthshock which killed off Adric.

Continuity

 * The Doctor mentions that he has visited all three Atlantis’. (DW: The Underwater Menace, The Daemons, The Time Monster)
 * The Doctor calls the evil Entity Fred. He had previously attributed this name to a Robot Yeti, (DW: The Web of Fear) and Romana I. (DW: The Ribos Operation)
 * Katie would later be resurrected by the Mitahi. (DW: Ashes to Ashes, Dust to Dust)

Home Video Releases
To be added.