A doctor (Ronald Howard) and his wife (Mary Laura Wood) have a loveless marriage, only she will not give him a divorce. Her sister (Olga Edwardes) arrives to work for him and his wife uses their affair to sue for divorce. On the day she is leaving for a new life, she is killed and the husband is charged of her murder. The sister and his friend (Eric Blair) set out to prove his innocence. This is a typical british mystery fom the 1950's.