Still recovering from serious head injuries sustained in a car crash, motor racing driver Alan Colby and his wife Denise go on holiday to the South of France. There, Alan is suddenly and unexpectedly struck with a compulsion to strangle his wife. Hearing about this, Dr. David Prade, a local psychiatrist, offers to help, but his offer is rejected by Alan and he and Denise return to London. The psychiatrist follows them there, convinced that sooner or later his services will be needed and that he should be close at hand. At first, all seems well with Alan, but then one morning he wakes from a long sleep to find that Denise has disappeared. Worse, all the evidence points to his having murdered her.
Beautifully filmed in black-and-white MegaScope by the great Gil Taylor and masterfully directed by Guest, who was always at his best working on suspense films, "The Full Treatment" is a minor classic.