A bipolar, bigoted, junkie cop manipulates and hallucinates his way through the festive period, until he finally meets his match… himself. Scheming Bruce Robertson (James McAvoy in a standout performance), a bigoted and corrupt policeman, is in line for a promotion and will stop at nothing to get what he wants. Enlisted to solve a brutal murder and threatened by the aspirations of his colleagues, Bruce sets about ensuring their ruin.As he turns his colleagues against one another by stealing their wives and exposing their secrets, Bruce starts to lose himself in a web of deceit that he can no longer control. His past is slowly catching up with him; a crippling drug habit and suspicious colleagues start to take their toll on his sanity. The question is: can he keep his grip on reality long enough to disentangle himself from the filth?