Similar to Batman and the Blue Beetle (Ted Kord), Spy Smasher (real name Alan Armstrong) is a master detective, equipped with a number of gadgets and a specialized vehicle, the "Gyrosub", which was a combination airplane, automobile, and submarine. Created by Bill Parker and C. C. Beck, Spy Smasher was introduced in Whiz Comics #2 (February 1940). Alongside Captain Marvel, Spy Smasher became one of the magazine's most popular characters. in Whiz Comics #16-18, he was briefly an opponent of Captain Marvel, as a Nazi Scientist and old enemy of his, the Mask, used a device to brainwash him, but finally Captain Marvel was able to restore his mind.

His name was changed to Crime Smasher after World War II ended, and the first issue of Crime Smasher was published in 1948. In 1953, Fawcett ceased publication of all superhero comics, after settling a lawsuit against DC Comics over Captain Marvel being an infringement on the copyright of Superman, agreeing to cease publishing Captain Marvel.

After DC Comics obtained the rights to the Fawcett characters in 1972, Spy Smasher began appearing irregularly in DC Comics, presented as one of the heroes of Earth-S prior to Crisis on Infinite Earths. He first appeared in Crisis in Eternity, as a member of the Squadron of Justice when King Kull had captured Shazam and the Elders, and teamed up with other villains to wipe out life on all three Earths, and defeated Ibac on Earth-Two as he attacked Atlantis by tricking him into saying 'I back down from no-one,' defeating him as saying his name causes him to turn into a normal man and vice versa. The character was used prominently in the 1990s series The Power of Shazam!, in which aged Alan Armstrong often recounts his adventures as Spy Smasher. Power of Shazam! #24 was dedicated to Armstrong's recounting of a Cold War-era mission he undertook with an archaeologist named C.C. Batson to Batson's children, Billy (alter-ego of Captain Marvel) and Mary (alter-ego of Mary Marvel).

While Alan was still Spy Smasher in that story, a crossover between Power of Shazam and Starman in 1997 included Jack Knight running over the history of the Fawcett City heroes, and mentioning that he thought Spy Smasher became Crime Smasher after the war but was unsure.

AC Comics has published reprints of some Golden Age Spy Smasher stories that have lapsed into the public domain. The character also made a cameo appearance the inaugural issue of Image Comics' Next Issue Project.