X-13 Agent Secret
From 1960 to 1986, Impéria published X-13 Agent Secret, a long-running spy-thriller series that ran for 442 issues, chronicling the globe-trotting missions of a lone operative whose code name became synonymous with Cold War-era intrigue. The series was a staple of the publisher's espionage line, blending gadget-heavy action with shadowy conspiracies, and is best remembered for the taut, cinematic storytelling of its longest-running writer, Jean-Claude Duvalier, whose work defined the character's stoic, resourceful persona. Though never breaking into the mainstream superhero market, X-13 Agent Secret earned a devoted readership for its gritty, grounded take on international espionage, influencing later European comics with its moody, realistic art and labyrinthine plots.