A young man is beaten and thrown from a liner into New York Harbor by a bunch of crooks he was in with. Though left for dead, he survives with memory loss. A rich girl takes a love interest in him, but his ex-comrades still try to kill him.
Mike learns through a classified ad that his parents are looking for him, he goes to meet them and his fiancée.They warmly take him back, but something is not quite right about them, and soon he realizes he's being set up.
At a New York College , Alden is the focus of experiments to overcome amnesia, but he must share a dorm room with students and earn his keep by working shifts at campus security, but this puts him in conflict with protesting students.
A mysterious photograph of a funeral reception for a murdered girl shows Alden present.Though a young man was convicted, and Alden has no memory of the event, he suspects he might be the actual killer.
Anthony is lured to a strange apartment by a naval officer, where he finds a girl in a harem costume. Later he's accused of murdering the officer by the police when his body is found in a room where his finger prints are found.
Alden makes arrangements to pay a man $2000 for his true identity, but both are pursued by ruthless hit men. A troubled boy joins him hiding out in Central Park, unable to face home responsibilities after his father dies.
A reluctant girl is used as a medium in a magic act, and a blue coronet is part of her costume. This intrigues Mike and Tony, who find the magician a strange and probably psychotic devil worshiper who won't let the girl go.
Feds want to exploit Alden's amnesia for simulating a mission to Mars. Brainwashed, he and a partner are placed into a drug-induced simulator. His partner's breakdown aborts the mission, just as Michael begins to remember parts of his past.
Alden hears a pop tune on the radio, supposedly from a dead singer, yet never released until that moment-but he somehow knows the lyrics already, and surmises that he had to have been present at the recording session. Tony joins him as they pressure the dead star's producer for information.
Michael spies an Asian girl whom he believes he met with in his forgotten past. Following her leads to brutes, discovering he knows karate, a dojo instructor who mentors him, confused memories, cleared memories and a martial arts finish.