If you've heard of comic book superheroes, you haven't necessarily heard of Alan Moore. This is a shame. The good Mr Moore has arguably done more to revolutionise the comic book industry, and make it a more socially acceptable medium, than any other individual. Unfortunately, no one's really noticed.
It started, for Americans, in 1985 with the publication of Watchmen. The story is set in a more realistic world where vigilantes have been outlawed, except three that work for the government. When one of those operatives is murdered, and the rest of the superhero community appears to be falling apart, it seems they have a 'masked killer' on their hands. The truth, however, is far more horrifying. While the plot is amazing, the complexities of it go far beyond the mere story. There is foreshadowing, symbolism and parallelism. Alan Moore as writer and Dave Gibbons as artist set about to purposefully make the story use the medium of sequential art (comic books) to the fullest extent. As Moore has stated, with comics one can control everything to the finest detail - every word and every image that the reader sees. This cannot be duplicated to the same extent in any other medium.
Another work, and arguably a companion piece to Watchmen is Moore's work that was originally published in Britain as a serial in Warrior Magazine, then later picked up and continued by DC Comics in America. It is called V for Vendetta (V4V), and it is the story of anarchy. In V4V's future, Britain has survived a worldwide nuclear war, and in the aftermath, becomes subjugated by Norsefire, a fascist political party. The story follows someone named V as he/she systematically overthrows the government in an attempt to let the people live their lives for themselves. Like Watchmen, it is done almost entirely without narration or word balloons. And while there are masks and superpowers, there is no denying the V4V is an intellectual work of literature, not mere spandex and explosions.
Another work of importance is MarvelMan1. It is the relaunch of a popular British superhero, but treats it, once again, as adult entertainment (not porn), instead of kid stuff. Moore's work is on a different level, resembling illustrated novels more than anything else. If word could spread, it would help comics reach whole new audiences, something the medium desperately needs.