Synopsis: Sgt. Renfrew and Constable Kelly are traveling upriver on a cargo freighter when they meet Ann, a mysterious and charming young woman who -- unbeknownst to them -- is part of a gang that plans to steal the freighter's gold shipment. After she tricks them into getting locked in the cargo hold, Ann and her friends take off with the gold. When Kelly is wounded by gunfire, Renfrew goes after the double-crossing thieves on his own.