Synopsis by Hal Erickson
This typically hard-nosed Jack Holt vehicle casts the star as opium smuggler Tom Fellows. While in Shanghai on "business," Tom rescues Mary Blake (Dorothy Revier) from the clutches of his deadly rival London Charlie (Pat Harmon). But Mary can't stay out of trouble, obliging Tom to rescue her a second time. Several hairbreadth escapes later, Mary reveals herself to be "Secret Agent 63" -- whereupon Tom identifies himself as British Intelligence Officer Robert Wellesley, Mary's boss! Blessed with one fast-action scene after another, The Warning can perhaps be forgiven for its nonsensical storyline.
agent [representative], arrest, battle [war], Britain, capture, drugs, gangster, intelligence [gov't], rescue, secrets, subterranean, weapons