Maxwell Mutt might be small, but his heart is big and the city is full of adventure. Before long, he teams up with a gang of downtown dogs: Restreppo the retired police-dog, Mr B the homely bulldog and Madison the angry poodle (do not mention his hairdo). When Maxwell hears the call of a friend in need, the dogs brave the big, bright city, where they hear tales of the Collector; the cruellest ever dog-catcher! But dreams, fun and adventure are waiting along the way.