British horror classic from Michael Reeves, the acclaimed director of 'Witchfinder General'. Mike Roscoe (Ian Ogilvy) is a young man bored with the swinging scene of 1960s London and eager to try a new kind of kick. He certainly finds something new when he meets Professor Montserrat (Boris Karloff), a hypnotist who has developed a way of both controlling the minds and sharing the sensations of those he hypnotises. Montserrat, along with his wife Estelle, try out the technique on Mike and greatly enjoy the experience of 'being' a young man. But the experience is addictive, and things soon get out of control.