The beautiful daughter of a wealthy industrialist turns up drunk and unconscious in a hotel room. To avoid a scandal the hotel house detective hires his former partner, private detective Tony Rome, to sober her up and escort her home. The next day, the girl's diamond pin is mysteriously missing. Arriving back at his houseboat, Tony is greeted by a pair of thugs who knock him out and tear his boat apart, desperate to find the pin. Tony's problems are just beginning, When he gets to his office he's in for a grisly surprise. His ex-partner is waiting for him with a bullet through his head.