Rough Ridin' Justice (movie, 1945)

Steve Holden (Charles Starrett) and his men successfully raid a wagon train. Among the local ranchers who decide to stop the raiding are Virgil Trent (Wheeler Oakman) and his daughter Gail (Betty Jane Graham). At a meeting, Sidney Padgett (Forrest Taylor), Cannonball (Dub Taylor) and other townspeople conclude that someone is tipping the gang off on important shipments. Trent volunteers to contact the outlaws. He meets Steve and persuades him to cross to the side of the law and protect the ranchers. Steve soon suspects Padgett and tricks him into revealing his identity as the secret leader of the bandits, and in a furious battle between Steve's men and the outlaws, the former win.