'Sin City 2' is finally happening after years of rumors and we've got proof today as one of the film's stars tweeted some photos from the set. Crystal McCahill, Playboy model, has joined the cast and posted some photos of her 'Sin City 2' character. As you might expect, she looks pretty good.

McCahill - Playboy's Miss May, 2009 - was added to the cast of Robert Rodriguez's 'Sin City: A Dame to Kill For' and had been dropping some sly tweets throughout the past month. But eventually she dropped the ruse and let the cat out of the bag:

So we don't know who McCahill will be playing in the film (we'll go out on a limb and guess that a Playboy centerfold probably doesn't have a lead role) but that she has her scene with Rourke's Marv. We do however have a look at who McCahill will be playing in the film. The actress took a snap of a promotional still (that looks remarkably like the poster used for 'Machete Kills') and posted it to Instagram.

'Sin City 2' is set for a release later this year with a cast that includes Rourke, Jessica Alba, Rosario Dawson, Jaime King, Jamie Chung and Dennis Haysbert. The film's two big roles - Ava and Dwight (originally played by Clive Owen) - have yet to be cast or have at least not yet been announced.