Director: Zack Snyder
In an alternate 1985 America, costumed superheroes are part of everyday life. When one of his former comrades (Jeffrey Dean Morgan) is murdered, masked vigilante Rorschach (Jackie Earle Haley) uncovers a plot to kill and discredit all past and present superheroes. As he reconnects with his retired associates (Patrick Wilson, Malin Akerman and Matthew Goode), only one of which has true powers (Billy Crudup), Rorschach glimpses a far-reaching conspiracy involving their shared past and catastrophic consequences for the world's future.
- Walter Addison [Lee Iacocca]
- Jay Brazeau [New Vendor]
- Chris Burns [Dumb Thug]
- Douglas Chapman [Ross Chess/Prisoner on fire]
- Matt Frewer [Egard Jacobi/Moloch]
- Jackie Earle Haley ][Walter Kovacs/Rorscach]
- Rob LaBelle [Wally Weaver]
- David MacKay [Child Murderer]
- Stephen McHattie [Hollis Mason/Nite Owl I] (director's cut only)
- Jeffrey Dean Morgan [Edward Blake/The Comedian]
- Dan Payne [Dollar Bill]
- Jesse Reid [Teen at Newsstand]
- Patrick Sabongui [Knot Top Gang Leader]
- Malcolm Scott [Fat Thug]
- Manoj Sood [Karnak Scientist]
- Brett Stimely [President John F. Kennedy]
- William S. Taylor [Prison Psychiatrist]
- John Tench [Knot Top Gang Member]
- Danny Wattley [Huge Prisoner]
- Patrick Wilson [Dan Dreiberg/Nite Owl II] (dream sequence)
- Danny Woodburn [Big Figure]
- Malin Akerman [Laurie Jupiter/Silk Spectre II] (dream sequence)
- Nhi Dho [Vietnamese Girl]
- Leah Gibson [Silhouette's GIrlfriend]
- Carmen Lavigne [Anti-War Protestor]
- Laura Mennell [Janie Slater]
- Sonya Salomaa [Adrian Veidt's Assistant]
- Apollonia Vanova [Silhouette]
- Lori Watt [Rorschach’s Mother]
- Was shipped to some theaters under the codename "Old Heroes Never Die".
- All of the U.S. flags in the film have 51 stars, because in the film's alternate history, Vietnam became the 51st state after America won the Vietnam War.
- Jackie Earle Haley was the only one of the main actors who was already familiar with the comic book. He actively campaigned for the part of Rorschach. Although Jackie Earle Haley has a black belt in Kenpo, he chose not to draw on those skills in his fight scenes, as he felt that Rorscharch would have fought in a scrappier, less disciplined style.
- Zack Snyder found casting for The Comedian to be a difficult process, as the character is gruff and grizzled. Most of the actors he met with he felt were too groomed. Jeffrey Dean Morgan was very grumpy during his meeting with Snyder, something that appealed to him a great deal.
- The first trailer for the film, which premiered with The Dark Knight (2008) sparked so much interest that it sent the graphic novel back onto the bestseller list. Barnes and Noble Bookstores reported selling out of the novel nationwide.
- When Patrick Wilson was offered the role of Dan Dreiberg, he called one of his best friends who is a huge comic book fan, and asked him what he knew about the Watchmen comic. He told Patrick that if he was ever to do a superhero movie that this was the one to do. Having gotten the part, Patrick invited his friend to visit the set when filming the prison escape scene.
- During the opening credits, the original Nite Owl stops a mugging. There are Batman comic book covers and Fleidermaus posters hanging on the wall of the alley. It can be assumed the people he saves from being accosted are Thomas and Martha Wayne, parents of Bruce Wayne, who are coming out of the theater. This is further implied by a poster with the word "GOTHAM" on it. Gotham is the city in which Batman operates, but since his parents lived, there's no need for Bruce Wayne to become Batman in the Watchmen universe.