- Country: USA
- Genres: Action, Comedy, Drama
- Release: 1942-10-23
- Director: Lesley Selander
- Writers: J. Benton Cheney , Clarence E. Mulford
- Language: Spanish | English
- Stars: William Boyd , Andy Clyde , Jay Kirby , Antonio Moreno , Nora Lane , Chris-Pin Martin , Esther Estrella , John Vosper , Eva Puig , Alan Baldwin
- Runtime: 68 min
- Awards: N/A
- AKA: Guldrøverne fra Mexico (Denmark) , Hevnens dal (Norway) , Undercover Man , El protector (Argentina) , Undercover Man (United Kingdom) , Spökryttaren (Sweden) , Undercover Man (United States of America) , O Protetor (Brazil) , Nattens mysterier (Denmark)
- Plot: Hoppy is sent for to see if he can find the outlaw gang working both sides of the border. The gang leader, sometimes dressed as Hoppy and sometimes as Gonzales, has the two sides suspecting each other. But finding an old wanted poster, Hoppy sets a trap.
- IMDB:tt0035487
Undercover Man Cast · · · ALL
Lesley Selander
Director
William Boyd
Hopalong Cassidy
Andy Clyde
California Carlson
Jay Kirby
Breezy Travers
Antonio Moreno
Tomas Gonzales
Chris-Pin Martin
Miguel
Nora Lane
Louise Saunders
Alan Baldwin
Bob Saunders
Eva Puig
Rosita Lopez
Jack Rockwell
Captain John Hawkins
John Vosper
Ranger Ed Carson
Pierce Lyden
Bert, lead raider
Tony Roux
Senor Chavez
Martin Garralaga
Senor Cortez
Earle Hodgins
Sheriff Blackton
Ted Wells
Jim Wilson
Cliff Parkinson
Cook, Jim's Partner
Joe De La Cruz
Injured Man, interrupts party
Ben Corbett
Outlaw Ambusher
Frank Ellis
Henchman
Horace B. Carpenter
Party Guest
George Morrell
Party Guest
Joe Dominguez
Caballero
Al Haskell
Caballero
George Sowards
Cowhand
Lem Sowards
Cowhand