The Card Player (2003) - Dario Argento.

This tricky noughties giallo features a degenerate serial killing card player who likes to poker face with a Stanley knife!!!!! Often unfairly maligned by those clearly not operating with a full deck, Argento keeps the killer's identity close to his chest, and his two handsome, charismatic cops prove entirely sympathetic. This slick, frequently inventive Italian blood-spiller is given an additional adrenaline boost by another exciting electronic score by maestro Claudio Simonetti! Not without flaws, what's good is certainly good enough, and I've grown to appreciate the somewhat bizarre Penelope Pit Stop climax!