Watchmen is a twelve-issue comic book limited series written by Alan Moore and illustrated by Dave Gibbons. Originally published by DC Comics as a monthly limited series from 1986 to 1987, it was later republished as a trade paperback, which popularized the "graphic novel" format. To date, Watchmen remains the only graphic novel to win a Hugo Award, and is also the only graphic novel to appear on Time Magazine's 2005 list of "the 100 best English-language novels from 1923 to the present." Watchmen is set in 1985, in an alternative history United States where costumed adventurers are real and the country is edging closer to a nuclear war with the Soviet Union (the Doomsday Clock is at five minutes to midnight). It tells the story of a group of past and present superheroes and the events surrounding the mysterious murder of one of their own. Watchmen depicts superheroes as real people who must confront ethical and personal issues, who struggle with neuroses and failings, and who - with one notable exception - lack anything recognizable as super powers. Watchmen's deconstruction of the conventional superhero archetype, combined with its innovative adaptation of cinematic techniques and heavy use of symbolism, multi-layered dialogue, and metafiction, has influenced both comics and film.

Alan Moore, who wanted to transcend the perceptions of the comic book medium as something juvenile, created Watchmen as an attempt to make "a superhero Moby-Dick; something that had that sort of weight, that sort of density." Moore also named William S. Burroughs as one of his "main influences" during the conception of Watchmen and admired Burroughs' use of "repeated symbols that would become laden with meaning" in Burroughs's one and only comic strip, which appeared in the British underground magazine Cyclops.[4] Moore and Gibbons originally conceived of a story that would take "familiar old-fashioned superheroes into a completely new realm." Initially, Moore looked towards the defunct MLJ Comics line of superheroes for inspiration.

"I'd just started thinking about using the MLJ characters — the Archie super-heroes - just because they weren't being published at that time, and for all I knew, they might've been up for grabs. The initial concept would've had the 1960s-'70s rather lame version of the Shield being found dead in the harbor, and then you'd probably have various other characters, including Jack Kirby's Private Strong, being drafted back in, and a murder mystery unfolding. I suppose I was just thinking, "That'd be a good way to start a comic book: have a famous super-hero found dead." As the mystery unraveled, we would be led deeper and deeper into the real heart of this super-hero's world, and show a reality that was very different to the general public image of the super-hero. So, that was the idea." Dick Giordano, who had worked for Charlton Comics, suggested using a cast of old Charlton characters that had recently been acquired by DC. However, the Charlton heroes were being slowly integrated into the normal DC continuity. Because Moore and Gibbons wanted to do a serious storyline in which some of the newly acquired characters would die, using the Charlton heroes was not feasible.

Giordano then suggested that Moore and Gibbons simply start from scratch and create their own characters. So while certain characters in Watchmen are loosely based upon the Charlton characters (such as Dr. Manhattan, who was inspired by Captain Atom; Rorschach, who was based upon the Question; and Nite Owl, who was loosely based on the Blue Beetle), Moore decided to create characters that ultimately would scarcely resemble their Charlton counterparts. Originally, Moore and Gibbons had enough plot for only six issues, so they compensated "by interspersing the more plot-driven issues with issues that gave kind of a biographical portrait of one of the main characters." During the process, Gibbons had a great deal of autonomy in developing the visual look of Watchmen and inserted details that Moore admits he did not notice until later, as Watchmen was written to be read and fully understood only after several readings.