"Sin City 2" has been in the works almost from the moment the original film became a surprise hit in 2005. Utilizing green-screen sets and a large array of actors like Clive Owen and Mickey Rourke, the film was the first to recreate Miller's distinctive style on the silver screen; Miller was even invited to participate as a co-director. The film earned $100 million worldwide.
Since that time, Rodriguez has kept the sequel as part of his revolving development roster alongside "Spy Kids" sequels and "Grindhouse" spin-offs like "Machete." At one time, the project was reportedly near production with Angelina Jolie set to star as Ava from "A Dame to Kill For," the second "Sin City" story which, according to reports, would serve as the spine of the sequel.
It is unclear if the production team will in fact use "A Dame to Kill For" as its primary source or if Miller and Rodriguez have selected other tales from the series. At one time, Miller suggested he was working on a new story featuring the Nancy Callahan character (played by Jessica Alba in the film) specifically for the sequel.
Monahan won an Academy Award for Best Adapted Screenplay in 2006 for "The Departed," so he has plenty of experience with massaging previously existing material into a film format, but time will tell if the writer can also massage Miller's idiosyncratic style.