Corporal Larry Grant and Sergeant "Mac" McGowan, of the United States Marine Corps, are rival for the love of Frances Schiller, but team up to hunt down "The Tiger Shark," a mad, scientific wizard who is holding Sergeant William Schiller, Frances' brother, a prisoner on a wild, jungle island in the Pacific.

Shortly after Moody Pierson saves Sheriff Tim's life, Moody is arrested for murder. Tim doesn't believe he did it and lets him get away. Kicked out as Sheriff, Tim goes after the real kiler and this leads him to the town controlled by Red Slavins.

A mysterious bandit known as "The Wolf" steals the payroll from a country ranch.

Gangster Chandler and his accomplice Tracy arrive at a dude ranch. Cowboy Kentucky arrives at the same time. When Tracy double-crosses his boss and has the stage robbed, Kentucky finds the outlaws and brings them in. Tracy frames him for the murder of the driver but his pal Cactus gets him out of jail. He returns just as Chandler shoots Tracy and Kentucky finds himself arrested for another murder.