The Village (The Prisoner)
Both the original 1960s TV series and its modern remake shared a flair for the strange and terrifying when it came to The Village, a mysterious seaside town populated by former government agents who have been brought there for unknown reasons. Separated from the rest of the world by a dangerous mountain range, The Village offers more than just natural obstacles to escape. There's also the threat of bizarre, white, balloon-like "guards" that do terrible things to prisoners on the run. Combine all of this with ample use of hallucinogenic drugs and torture devices, and you've got a sci-fi prison worse than anything you find in space.