Drake takes the place of a British citizen defecting to the East, in order to discover where all these English communists are disappearing to. Once at his destination, he discovers that, in a way, he never really left.
One of the better episodes, with a especially nastily fey perfromance from Arne. Also a very bleak ending, all the more bleaker for its sublety. One can easily see this as being the source for "The Village" in The Prisoner. Also the obvious inspiration for the awful 1989 John Travolta movie The Experts. One does wonder how secret an English village popping up in Siberia would be, though. I'm sure U-2s and satellities would take notice!