The movie starts with a man in a basement with his dog, and then he transfers his dog to a parallel universe, and then the dog comes back. Then two friends come to visit him in the basement, and then the door transfers again but they don't go back. So the two friends are transferred after the dog, to where they can meet themselves there (but not the same) and since it's not safe to meet themselves, they need to come back in the same day.
But then, there one of the friends meets his wife, that is his wife there, but he died in a war on this world. The other man is a doctor in a hospital in this world, who has something implanted in his head. The last one is a fat man, and the police are after him since fat people not allowed to be in public.
At some point in the movie the fat man is forced to move to the forest out of the city where all the fat people are.
The other one falls in love with his wife in this world.
The last one finds out he should play in a game (a TV game) where everyone is after him to kill him, and then he runs away.
I also remember that in the parallel universe all the cars were white and the same model, and everyone can drive a car that is free.