For 15 years, Karan Mehra (Dev Anand) had believed that his father was dead. Then his mother told him the truth, that his father was convicted for murder & was serving a prison term. With only childhood memories of his father, as a kind loving & gentle man, Karan believed his father was innocent. He sets on an unusual non-violent path to prove his father's innocence. During this he falls in love with an officer working for a newspaper (Madhubala) which he visits for newspaper article reference. While his search for witnesses brings him to some people, where he meets the prostitute who was the key witness to the murder in which his father was accured. The mystery then unfolds.