G-Men learn that "Victor Brenda", a notorious jewel thief, is heading for the US, to steal the Belgravian crown jewels currently on exhibit. The jewels are placed on a ship bound for Belgravia. However, the guard is murdered and the treasures are stolen. Agent Dexter, alias Agent X-9, trails Blackstone, one of the gang members, who hides the jewels in a safe deposit vault of a bank. He takes the bank receipt to an art shop, where Marker, a paid accomplice, conceals it between an oil painting and its frame. Dexter arrests Blackstone and pursues Marker with the full intention of unmasking Brenda.

• Scott Kolk as Agent Dexter (X-9)
• Jean Rogers as Shara Graustark
• Henry Brandon as Blackstone/Victor T. Brenda
• David Oliver as Pidge
• Monte Blue as Baron Michael Karsten
• Lon Chaney Jr. as Maroni, primary henchman
• Ben Hewlett as Scarlett, primary henchman
• Larry J. Blake as Chief FBI Agent Wheeler
• Henry Hunter as FBI Agent Tommy Dawson (C-5)
• George Shelley as Packard, a henchman
• Lynn Gilbert as Rose, gun moll
• Robert Dalton as Thurston
• Leonard Lord as Ransom, dissident henchman
• Bob Kortman as "Trader" Delaney
• Eddy Waller as Lawyer Carp
• Si Jenks as "Jolly Roger", ticket barker

Secret Agent X-9 was based on the comic strip by Dashiell Hammett (writer) and Alex Raymond (artist).

Stunts edit

• George Magrill
• Eddie Parker doubling Scott Kolk
• Tom Steele doubling Henry Brandon & Jack Cheatham

1. Modern Pirates
2. The Ray That Blinds
3. The Man of Many Faces
4. The Listening Shadow
5. False Fires
6. The Dragnet
7. Sealed Lips
8. Exhibit A
9. The Masquerader
10. The Forced Lie
11. The Enemy Camp
12. Crime Does Not Pay

_Source:^[1]

• Secret Agent X-9 at IMDb