"We're not like you - we can't be whole on our own."

Seeking respite after the traumatic events in the thirtieth century, the Doctor and Chris travel to 1950s London. But all is not well in bohemian Soho: racist attacks shatter the peace; gangs struggle for territory; and a bloodthirsty driverless cab stalks the night.

While Chris enjoys himself at the mysterious and exclusive Tropics club, the Doctor investigates a series of ritualistic murders with an uncommon link — the victims all have no past. Meanwhile, a West End gangster is planning to clean up the town, apparently with the help of the Devil himself. And, in the quiet corridors of an abandoned mental hospital, an enigmatic psychiatrist is conducting some very bad therapy indeed.

As the stakes are raised, healing turns to killing, old friends appear in the strangest places — and even toys can have a sinister purpose.