A
gangster who operates a sleazy
dance hall uses a sadistic
bodyguard to keep his girls afraid and his customers in line. A
merchant marine seaman is found murdered at the place and suspicion quickly falls upon the operator of a
dime-a-dance honky tonk joint. A
federal undercover agent is planted in the place to gather evidence, and he soon learns that the dive is only a cover-up for diamond-smuggling activities, and that one of the operation's henchmen, who is handy with a
switch-blade knife, is the actual killer. Before they can be arrested, the henchman kills his boss and is shot while trying to escape. ==Cast==