After intrepid working girl Mary Carter becomes the new owner of a reputedly haunted mansion located on Black Island near the Cuban coast, a stranger phones warning her to stay away from the castle. Undaunted, Mary sets sail for Cuba with a stowaway in her trunk—wise-cracking Larry Lawrence, a radio announcer who helps Mary get to the bottom of the voodoo magic, zombies and ghosts that supposedly curse the spooky estate.
After living all his chilhood in the street, a young boy notices rapidly that crime doesn't pay and that´s why he decides to become a policeman. One day, one of his best friends go in prison for a murder he didn't commit. Immediately the policeman tries his best to release him and prove his innocence.
Jim Joyce runs a garage with old Abner Hope. When Hope's granddaughter, Mary Ellen, comes to visit, Joyce falls in love with her. Joyce has a number of bizarre inventions and he dreams of harnessing the nearby falls for power, but he can't get any financing from the town banker.
