Roots: There are references to Armchair Theatre, Terminator, Summer Holiday, J. R. R. Tolkien, Freud, Wrigley's, Kodak, Gordon's gin, Virgin Megastore, Burger King, Durex, Silent Spring, The Avengers (Chubby mistakes Sam for Venus Smith), Churchill, Sean Connery, Julius Caesar, Frankenstein, Aleister Crowley's The Book of the Law, Dixon of Dock Green, Brylcreem, Macbeth, Star Trek, Rolls-Royce, Blackadder the Third, Special Brew, Batman, Schweppes, William G. Stewart and Fifteen to One, Bambi, James Bond, Wolseley 1500s, and Aston Martins.
Dialogue Disasters: "You're all dead! Meat and maggots in my death cave!"
Dialogue Triumphs: "I'm delighted to meet you, Mrs. Kreiner. Your son seems virtuous and trustworthy."
Continuity: The Beast are floating, intangible parasites with nozzle-like mouths, that attach themselves unknown to other beings. They are pan-dimensional and sentient, with limited intelligence. They feed on other species, eventually moving on to another when they are sated. Contrary to what the Benelisans believe, the Beast didn't wipe them out - the dimensional portals that opened on their planet did, the Beast merely taking advantage of them to reach Benelisa. Infestation by the Beast is only dangerous to species with populations too small to support them.
The Benelisans hail from the planet Benelisa, a planet anchoring a collection of spatiotemporal dimensional interfaces, due to the various black holes, white holes and other physical anomalies in that sector of space, which had an effect on their evolution. They used organic computers and much of their technology was based around crystallography (see Terror of the Zygons). They created a program designed to allow brains to interface with, and thus destroy, the Beast, which were ultimately responsible for the Benelisans' destruction. The program is delivered via leech-like, programmed biosynthetic organisms. They grow rapidly once removed from their host. They transmit retroviral RNA into the host DNA, which rewrites their DNA, causing guanine and cytosine to bind with a non-nitrogenous base. The organism also rewrites neural pathways in the host brain, resulting in their apparent schizophrenia. The Benelisan program, via the organisms, is designed to reformat the host brain, allowing them to interface with the Beast. The program, when implemented correctly, is communicable. Azoth is a Benelisan fluid droid with a featureless bronze sphere for a head, self-repairing circuitry, back-ups and fail-safes. His metal body was once covered in flesh. He is now so old that his memory has started to deteriorate beyond repair. His mission is to spread the Benelisan program on Earth, thus destroying the Beast. He arrived on Earth in 1822 and began infecting twins as test subjects, but was damaged and has been largely dormant until Roley gathered many of his test subjects together in one place, the resulting proximity resonances inadvertently reactivating him. If the program cannot be executed successfully, Azoth is programmed to implement a "Terminal solution", eliminating all life on Earth in order to wipe out the Beast by generating a bioelectrical pulse from his brain that increases exponentially.
The Doctor buys a begonia from Fitz for tuppence. He has built a metal carry-case containing a pocket dimension with zero gravity and an interface regulator in the clasp. He suffers a wound to his hand here, which heals rapidly. He connects Azoth's head to the TARDIS memory banks and downloads the contents of his memory wafers.
Fitz Kreiner is twenty-seven years old. His mother is called Muriel and was thirty-eight years old when she gave birth to him. Her maiden name was Tarr: her father, an only child, is buried in Highgate Cemetery. Fitz's great-great-grandfather on his mother's side was named Freddie and had an identical twin brother named Neville. Azoth experimented on Nevilla, who is still alive, fit and well here until Azoth breaks his neck. Fitz's father Otto was German. His father is deceased. Fitz was put into care when his mother got sick for the third time in a row. He smokes cigarettes. He currently works in Dr. Roley's garden centre, whilst his mother is one of Roley's patients. He lives in Archway. He dodged National Service. He is prone to daydreaming. He is also prone to lying outrageously when bored: when the Doctor first meets him, he is affecting a French accent. He owns and plays an electric guitar, and sometimes performs in Molly's club on Mercer Street. He has soft grey eyes and a slightly too long nose. He adopts the alias Fitz Fortune when performing, to avoid advertising the fact that his father was German. Fitz has a Benelisan leech in his neck, passed onto him by his mother. His mother dies here as a result of the Benelisan program, which she inherited from her great-grandfather and which is the cause of her mental illness. Fitz' joins the Doctor and Sam on board the TARDIS at the end.
Sam goes to an Italian restaurant (she orders a salad) and plays pool with Fitz. He kisses her after their night out, to her disgust. She later ends up almost naked with him in his bed after being knocked out, to her horror. She has been afraid of the mentally ill ever since she was a Brownie, when her group used to sing carols in mental hospitals at Christmas. Her grandma went senile. Azoth infects Sam with a Benelisa leech, thus infecting her with the Benelisan program; it fails to function correctly, allowing her to see the Beast and slowly killing her. The Doctor's uses information from Azoth's memory to reprogram the leech inside her, so that it repairs the damage it has caused and shuts itself down. Sam isn't sure whether or not there is a God.
The Doctor dumps Azoth's remains in a room in the TARDIS, that also contains bags of gold, tape recorders that use tiny discs, swimming pools, saunas, a 1957 stratocaster signed by Elvis, and a giant bed with a radio, a clock with no hands, and little spotlights built into the headboard.
Links: The Doctor notes that he spent some time in 1963 (An Unearthly Child). Sam thinks about Daleks (War of the Daleks). She worries that the Bel micro-organisms changed her in some way (Beltempest). Sam recalls Janus Prime (The Janus Conjunction), Belannia (Beltempest) and Proxima II (The Face-Eater). The Doctor mentions the Dalek Invasion (The Dalek Invasion of Earth).
Location: West Wycombe, Bethnal Green, and Archway, England, 1963; London, 2134.
Future History: The Beast have moved on from Earth by 2134.
Unrecorded Adventures: The Doctor implies that he knew Carl Jung.
The Bottom Line: "Things won't quite be the same, will they?" A vast improvement on Collier's previous Longest Day, The Taint has a complex plot, with superb characterisation (everyone, from Azoth to the Beast, has a decent motivation), a non-irritating Sam, and a proactive, intelligent Doctor. It is most memorable however for introducing Fitz, a hugely likable character from the start who isn't afraid to admit to his many failings, and would go on to beat Benny as the Doctor's longest serving companion in any media.