Frankie Thomas
— Tim Tyler
Frances Robinson
— Lora Lacey
Jack Mulhall
— Sgt. Gates
Al Shean
— Professor Tyler
Norman Willis
— Spider Webb
Anthony Warde
— Garry Drake
Earl Douglas
— Jules Lazarre
William Benedict
— Spud
Frank Mayo
— Jim Conway
Alan Gregg
— Brent
Stanley Blystone
— Capt. Clark
Everett Brown
— Mogu
Skippy
— JuJu
Ernie Adams
— Henchman Becker
Ed Brady
— Ivory Patrol Lieutenant
Al Bridge
— Capt. Trowbridge
Lane Chandler
— Patrolman Kelly
William Desmond
— Dock Official
Kenneth Harlan
— Spencer, Trader
Ethan Laidlaw
— Patrol Guard Rocky
William McClain
— Native
Chuck Morrison
— Henchman
Charles Murphy
— Henchman
Forbes Murray
— The Doctor
Pat J. O'Brien
— Patrolman Berry
Eddie Parker
— Henchman
Tom Steele
— Ivory Patrolman
Charles Sullivan
— River Boat Crewman / Henchman
Harry Wilson
— Henchman