Robert Rodriguez is never afraid to think outside the box. Just look at the latest casting news for 'Sin City 2' (dubbed 'A Dame to Kill For'). The film already has an impressive ensemble of A-list stars including Joseph Gordon-Levitt, Bruce Willis, Eva Green and Josh Brolin, but now the director has chosen Stacy Keach, perhaps best known as "Mike Hammer" in the '80s, to play a major villain in the sequel.

Find out exactly who Keach will be portraying after the break!

According to Variety, Keach will play mob boss Wallenquist, a character described by 'Sin City' writer and co-director Frank Miller as "the one man who can't be redeemed in Sin City. He is pure evil."

That's saying a lot when considering all of the sordid folks who call Sin City their home.

Digging a bit deeper thanks to Sin City Wiki, Wallenquist, aka "the Kraut," is said to be "the mysterious and powerful German-American leader of the Basin City mob. His goal is merely to achieve power and profit, regardless of what underhanded methods are necessary." His face is evidently replete with heavy scars and burn wounds.

Keach played Mickey Spillane's private detective "Mike Hammer" in a TV series and a couple of TV movies in the mid-'80s. Mike Hammer is a classic character of "film noir," and as 'Sin City' is firmly enmeshed in that genre, the casting is quite inspired. Keach is also well known for turns in 'Up in Smoke', 'American History X' and, most recently, 'The Bourne Legacy.'

Now shooting in Austin, Texas, 'Sin City: A Dame to Kill For' comes out on October 4th.

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