Because he spent his youth with a gang of thugs, a tennis champion is forced to help his former comrades rob his mistress's house. He opposes it and is seriously injured the day before a match, he loses it. The one he loves learns the truth and keeps her love for him.
Two police inspectors track down a mysterious criminal who signs his crimes with a fiery triangle. When they have just discovered an accomplice, one of the police officers, in love with the young girl, is shot dead. His colleague will then have only one goal in mind.
