Maxwell Reed stars as Chris Pelley, a blind ex-serviceman who is driven to the wrong address when he arrives in London and finds a corpse and a man's ring nearby. The three killers are still in the house but when they realise that he is blind, simply knock him out and put him out on the street. The police find him, after a simple bonk on the bonce, but don't believe him because they cannot find the body. Then, after his sight is miraculously restored by an operation, he sets off to find the body and the killers. He returns to the house to find kindly Pat Dale (Dinah Sheridan) living there with her father and a photo on the piano tells him the ring belongs to her brother, Norman (Basil Appleby), presumed dead after a plane crash a year ago. Pat agrees to help him investigate the mystery, and with handy aid from her and Norman's friend Chalky (Patric Doonan), he busts a smuggling gang.