Lucky (2004)

Ever have one of those lifetimes where nothing seems to go right? Failing cartoon writer, Millard Mudd, has sunk deep into one. Living hermit-like and existing on a strict alcohol diet, Mudd's world has collapsed. But one day everything changes when a dog named Lucky enters his life. You see, what makes Lucky no ordinary dog is his ability to talk. And what makes Lucky invaluable is his ability to teach Mudd how to write again. But what makes Lucky dangerous is his ability to get inside Mudd's head and turn him into a serial killer.