The stars of the Sin City prequel have been told not to discuss Angelina Jolie's possible involvement in the film.

Jolie has been linked to the graphic novel adaptation, A Dame To Kill For, but director Robert Rodriguez is keen to keep his big name star under wraps and he's told his cast members not to reveal any details.

Actress Rosario Dawson, who will reprise her character, GAIL, opposite other Sin City alumni Brittany Murphy and Jessica Alba, says, "The lead actress is going to be absolutely fabulous; but I can't tell you who it is."

But Dawson does reveal to Movies.com, "It's going to be the prequel to my segment in the first one, so you'll understand a little bit more what the argument was between (co-star) Clive Owen and my character."