Two partners, the ass and the fox, go to a forest to find food. On their way, they meet a lion. The cunning fox promises the lion that he can have the ass for dinner, but asks that his life be spared. Together, they trick the ass to fall into a pit. As soon as the ass was secured, the lion jumps at the fox, killing it for its meat and ends up having both.
Moral: Traitors must expect treachery.