This low-budget mystery thriller from the Hammer stable featured a young American (Robert Webber) who becomes involved in a car accident while in Britain.
When he wakes up, apparently in a hospital, he finds he has completely lost his memory. Even more baffling is the fact that an unknown benefactor has paid for his medical treatment and put a luxurious penthouse apartment at his disposal when he is ready to convalesce.
Before long, Mr Smith (as he calls himself) begins to hear voices when there is nobody there and finds a blood-covered knife in his London apartment and the dead body of a woman in his bathtub.
He is, in fact, the victim of two nasty characters who are framing him for murder. One of them is the mystery woman (Lelia Goldoni) on whom Smith has counted to help him regain his memory.
She feigns sympathy and cooperation, but all the while leads him to a confession of the crime.
But Mr Smith has a smart private detective (Maurice Denham) and a pretty nurse on his side.