It's just such a brilliant premise! It takes some time to prove its point (and after a while the story becomes a little tripe), but from the moment Baxter steps out from the screen to discover life - leaving pandemonium in his wake as the other film characters don't know what to do - the whole thing becomes instantly mesmerising. Like Wings of Desire if it was a full on comedy and the romance was more amusing, with one of Allen's most captivating handling of meta narratives.