Holt of the Secret Service (1941) was the 16th serial released by Columbia Pictures.

Plot
A murderous gang of counterfeiters has kidnapped John Severn, the U.S. government’s best engraver, who is being held against his will and is forced to print virtually undetectable phony cash. The United States Secret Service sends its toughest agent, Jack Holt, and his female partner, Kay Drew, after the gang. Holt and his boss Malloy decide to try to pass Holt off as escaped tough guy, Nick Farrel. Masquerading as the bickering Mr. and Mrs. Farrel, Holt and Drew manage to infiltrate the ruthless gang of thugs and the tough talk and action never stops from there on. Holt’s hunches lead him to the culprits and into trouble on a canoe ride and in an outlaw camp, as the action moves from the gang’s hideout in a lost canyon to a gambling ship on the high seas to a small island country where the gang hopes to escape U.S. extradition.

The brains heavy is a man named Lucky Arnold but he hides behind the facade of one of his loyal henchmen, Quist, to shield himself from the Secret Service, and lets another one of his men, Valden, do most of his dirty work. The island nation has its own pocket dictator who is also trying to rub out our hero. During the 15 episodes, Holt endures numerous brushes with death, emerging from all of them with nary a hair out of place nor a crease in his well-tailored business suit.

Cast
Jack Holt as SS Agent Jack Holt/Nick Farrel
Evelyn Brent as Kay Drew, R49
Montague Shaw as SS Chief John W. Malloy
Tristram Coffin as Ed Valdin
John Ward as Lucky Arnold
Ted Adams as Quist
Joe McGuinn as Crimp Evans
Edward Hearn as Agent Jim Layton
Ray Parsons as John Severn, engraver
Jack Cheatham as Agent Frank
Stanley Blystone as J. Garrity
Lynton Brent as Radio Operator 6X241
George Chesebro as Rankin, Garrity thug
Franklyn Farnum as Denny, Prison Guard
Pierce Lyden as Henchman
George Magrill as Henchman
Jack Perrin as Mutiny henchman
Stanley Price as Dent, Garrity thug
Buddy Roosevelt as Carew, henchman
Harry Tenbrook as Detour henchman
Al Thompson as Gambler
Dale Van Sickel as Slugger, henchman