Secret Agent X-9 was a comic strip created by writer Dashiell Hammett (The Maltese Falcon) and artist Alex Raymond (Flash Gordon). Syndicated by King Features, it ran from January 22, 1934 until February 10, 1996.
X-9 was a nameless agent who worked for a nameless agency. X-9 used the name "Dexter" in the first story ("It's not my name, but it'll do.") and kept using it or being called by it in later stories, but acquired the name "Phil Corrigan" in the 1940s; decades later, the strip was renamed Secret Agent Corrigan. The nameless agency was also briefly the FBI, but later references to it were dropped and the agency was once more nameless.
After four stories by Hammett, Alex Raymond illustrated two stories written by Don Moore and one written by Leslie Charteris, who continued with write three more illustrated by Charles Flanders . After Charteris left the strip in 1936, scripts were credited to a King Features house name, "Robert Storm". Nicholas Afonsky drew the strip for most of 1938, followed by Austin Briggs until 1940.
Mel Graff took over the art in 1940 and began writing the strip as well in 1942, devising the name Phil Corrigan. The name Phil Corrigan was inspired by Phil Cardigan, a character in one of Graff's earlier comic strips, The Adventures of Patsy.
Graff also gave X-9 more of a personal life, introducing Belinda "Linda" Reed as Corrigan's gal Friday and early romantic interest in 1940. Wilda Dorre (later Dorray), a beautiful, blonde mystery novelist, debuted in late 1944 as a romantic rival. Corrigan finally chooses Wilda in 1947. Graff provides Linda a happy ending as well, as she marries Phil's younger brother, Bing, who was introduced in 1945 and is Phil's partner through 1947. Both female characters inspired popular songs: "Linda" written by Jack Lawrence and "Wilda" written by Graff. Wilda and Phil marry in 1950, and the two have a daughter, Philda, in 1952.
Graff also created a series of often grotesque villains with colorful names, including Blue-Jaw (introduced in 1944), Goldplate (1945), Liver-Lips (1946, 1947), and Grape-Eyes (1947). There was also Corrigan's criminal lookalike, Phil Haze (1946). Additionally, Corrigan encountered the beautiful criminal businesswoman Bargain Benny (1954) and the endearing rogue Prince Iguana (1953). Corrigan also had two professional colleagues in addition to his brother: Joe Florida (1948) and Joe Otterfoot (1952). Otterfoot is the rare depiction of a Native American in comic strips of this period in that he is portrayed as intelligent, competent, witty and attractive enough for a female painter to seek him out as a male model. He is also unique for having an interracial romance with that painter.