Me or the Dog

Me or the Dog is a 2011 short film directed by Abner Pastoll, produced by Junyoung Jang and starring Edward Hogg, about a man who believes that his dog, Dudley, is talking to him. Martin Clunes plays the mischievous voice of the dog, who challenges his owner Tom with the prospect of him actually being a real talking dog, and in order to do so sets out to prove that Toms girlfriend is cheating on him.

Source: Wikipedia