As if there weren't already enough incentive to watch "Watchmen," The Hollywood Reporter announced Wednesday (August 8) that Carla Gugino will be joining the cast of Zack Snyder's epic adaptation of the classic graphic novel.

The 35-year-old actress will play Sally Jupiter, a.k.a. the Silk Spectre, a stripper-turned-heroine famed for her sexuality and part of the Minutemen, a ragtag group of vigilantes who preceded the Watchmen (see "Director Zack Snyder On 'Watchmen' Flick: 'I Don't Wanna Screw It Up' ").

In the gray world of Alan Moore's comic, Jupiter is one of the most morally ambiguous characters, a possible lesbian whose "mask" is her own sexuality. At one point, she is sexually assaulted by fellow hero the Comedian. This leads to a second, consensual encounter during which Jupiter's daughter — Laurie Juspeczyk, a.k.a. the second Silk Spectre (to be played by Malin Akerman) — is conceived. Despite his sadism and abusive tendencies, it is implied throughout the comic that Sally harbors feelings for the Comedian into old age.

Gugino will play Sally during all her varying ages throughout the film, as Snyder has indicated in the past that he will be using "aging" and "de-aging" technology rather than casting different actors.

The "Sin City" star joins a cast that already includes Jackie Earle Haley, Patrick Wilson, Matthew Goode and Billy Crudup (see " 'Watchmen' Cast Revealed: Billy Crudup, Jackie Earle Haley, More"). "Watchmen" is expected to begin filming in Canada this fall for a March 9 release.

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