Role in the filmEdit
Riley is the leader of a gang of street dogs. He is first seen arriving with his gang and saves Shadow, Sassy and Chance from Ashcan and Pete. He then tells Shadow and Sassy (Chance fled, thinking Riley's Gang were reinforcements) that it is unsafe to be around here because there are humans present, and humans are bad news.
Riley reveals that he hates all humans as well as human pets for mere association. This is because his potential owner (who had received him as a puppy for Christmas) abandoned him in a gutter. He starts to change his mind after Shadow rescues a boy named Tucker from a burning house. When he asks Shadow if a human would risk their life to save him, he tells Riley that his owner Peter would. He then agrees to escort Shadow and Sassy home. However, Riley isn't pleased when he sees Chance hanging with Delilah (they had sparked a romance together while his gang had left). Indignant, he tries to convince Delilah that Chance is a housepet, and she shouldn't be with him. She refuses to listen at first, but when Chance's unruly antics get him and Riley's Gang in trouble, Delilah reluctantly dumps him.
Riley is last seen leading Shadow and Sassy to the bridge, where he and the two housepets prepare to go their separate ways. Before they do, he tells Shadow that he'll keep in mind about what he had said about humans, to which Shadow replies, "Riley, you're all right." Presumably, he also allowed Delilah to quit his gang to be with Chance.