A movie serial in 12 Chapters: US naval officer Don Winslow is given command of Tangita Island, near Pearl Harbor, where a ring of saboteurs is trying to destroy ships carrying supplies to the troops stationed in the islands and sabotage the war effort under orders from an unknown leader.
as Cmdr. Don Winslow
as Mercedes Colby
as Spencer Merlin
as Lt. Red Pennington
as Misty Gaye
as Mike Splendor
as John Blake
as Paul Barsac
as Henchman Corley
as Henchman Spike
as Seaman Chapman
as Henchman Prindle
as The Scorpion
as Gang Radioman Barker
as Lt. Cdr. Grady
as Admiral Warburton [Ch. 1]
as The CINCUS [Ch. 1]
as Capt. Holding [Ch. 1]
as Enemy Sub Capt. Tranker [Ch. 1]
as Capt. Fairfield, of the "Batavia" [Chs. 1-2]
as Tangita Jim [Chs. 2, 10]
as Capt. Sanders, of the "Tarleton" [Chs. 3-4]
as Saboteur Kramer [Chs. 3-4]
as Lead Henchman at Mill [Ch. 5]
as Native Henchman at Mill [Ch. 5]
as Witch Doctor Koloka [Chs. 6-7]
as Sub Capt. Jackson [Chs. 7, 9]
as Sam Munn, henchman [Ch. 8]
as Henchman Butch [Ch. 8]
as Gang Chemist Taylor [Chs. 8-9]
as Taylor's Lab Assistant [Ch. 8]