Prior to the United States' involvement in World War II, the masked vigilante Spy Smasher fights Nazi agents operating within the US, led by the treacherous sabotage leader codenamed The Mask.

Kane Richmond
as Alan Armstrong / Jack Armstrong

Marguerite Chapman
as Eve Corby

Sam Flint
as Admiral Corby

Hans Schumm
as The Mask

Tristram Coffin
as Drake

Franco Corsaro
as Captain Pierre Durand

Hans von Morhart
as Captain Gerhardt

Georges Renavent
as Governor LeComte

Rudolph Anders
as Col. Von Kohr

Henry Zynda
as Ritter Lazar