G-Man Ted Riley is ordered to investigate happenings at Diamond Island, where a bogus Major Gray is reported engaged in manufacturing a new brand of secret gas for his own purposes. Riley blows up his motor boat just off the island and is picked up by Gray's men. On the island he discovers chemist Professor Baker (John Cowell) and his daughter, Anne, are held captive by Major Gray.

Genres

Cast

Lloyd Hughes

Ted 'Rip-Roaring' Riley

Marion Burns

Ann Baker

Grant Withers

Major Gray

Eddie Gribbon

Sparko - Henchman

Paul Ellis

Franko - Henchman

Kit Guard

Bruno - Henchman

Wilfred Lucas

Chief Martin