A character-driven drama seething with underworld decadence, Montana is set in the final days of an unraveling crime organization. The Boss (Robbie Coltrane) is losing control over his underlings, while Claire (Kyra Sedgwick), his best lieutenant and most loyal operative, is determined to put him back in the driver's seat. But Claire is left out in the cold when she and her partner, Nick (Stanley Tucci), are set up by Duncan (Philip Seymour Hoffman), the Boss's financial genius, for a murder they didn't commit. On the run and stuck with Kitty (Robin Tunney), the Boss's cocaine-sniffing mistress, Claire seeks refuge with one of the Boss's shady business associates (John Ritter). But when he turns out to be foe rather than friend, Claire finds herself heading for a final violent confrontation.