Dirty Bill is a bulldog featured in the film The Robber Kitten. He is a great bandit and the authorities are always in his search. Despite acting alone and not having a gang, he is very feared by the townsfolk due to his taste for violence. While he is looked for, he falls on Ambrose whom he takes for a real bandit and invites him to make a criminal duo. Ambrose tells him a false story where he extorts money. Dirty Bill betrays Ambrose and extorts his bag money (in fact, cookies); Ambrose finally finds out how dangerous and scary is it to be friends with a robber and runs away. Dirty Bill gets confused upon finding there wasn’t any money in the bag. The fate of Dirty Bill remains uncertain. He is voiced by Billy Bletcher.
- In Walt Disney's Comics and Stories issues 17 and 582, Dirty Bill is more generous and when he gets captured, he tells Ambrose to return home with the stolen money, and says that he doesn't want Ambrose to end up like those who break the law.