As you know, the film centers on a young girl named Baby Doll (Browning) who is sent away to a mental health institution by her stepfather. He intends to have her lobotomized in five days time, and the horror of that sends her and her fellow inmates planning for an escape in a twisted Alice in Wonderland world of adventure and ass-kicking. THR notes that Hamm's role is being kept under tight wraps, that he's only known to be playing someone named High Roller. But given what major role has yet to be cast, I'm willing to bet he's playing the stepfather. I wouldn't be surprised if we see Hamm doing a bit of Captain Hook duty, and popping up as the antagonist of the girls' dream world as well.
Between the cast, the concept, and the girl sized t-shirt, there's not much more Snyder could add to this film to make me long for 2011 more than I already do. But something tells me he'll find room for some 300 and Watchmen cast cameos, and then the wait will really become unbearable.