Operation: Proteus

Operation Proteus was the twentieth episode of season 0 of Doctor Who (otherwise known as Doctor Who Prologue), it featured Susan and The First Doctor before the events of An Unearthly Child.

Plot
Susan is listening to beat poetry at a milk bar when a man suddenly stumbles into the bar and explodes into a mass of protoplasm while babbling about King's Cross. She returns to the TARDIS to tell the Doctor, who goes to King's Cross station to investigate and locates a secret entrance to a government installation. There, he is captured by the alien being Raldonn who runs Operation Proteus for the British government. Some time ago his spaceship crashed on Earth, killing his co-pilot, without whom he cannot generate enough psychic power to depart from Earth. The British government "asked" for his help in their weapons research projects, and, concluding that he was on a planet of savages, Raldonn easily twisted the project to his own ends. He intends to mutate a human being into one of his own kind to provide himself with a new co-pilot, but his current serum is unstable and will convert only one out of a million humans. Therefore he had a group of college students brought to the installation on the pretense that they were testing medical vaccines; in fact, he injected them with the serum and released one to carry the toxin to the surface. Soon, everyone in the world will be infected, and at least one of the victims will be close enough to Raldonn's true species to provide him with the psychic energy he needs to escape from Earth. But as the virus spreads, Raldonn's previous failed experiments are driven mad by its effects, and attack and him. The Doctor uses Raldonn's equipment to develop a genetic stabiliser and releases it into King's Cross station. The stabiliser spreads through the Underground system and blankets the city, returning everything to normal.

Characters

 * First Doctor
 * Susan Foreman
 * Clive
 * Dick Ashley
 * Grove
 * Laura Daniels
 * The Minister
 * Raldonn

Continuity

 * Before the Doctor and Susan settled down in Shoreditch in 1963, they took a brief trip to St Albans on 17 December 1997 to ensure that the United Kingdom would remain safe during and after the 1960s. Unbeknownst to either of them, the Fourth Doctor and his companions Romana II and K9 Mark II were in the vicinity on the same day. The Little Things