Kelly Mangiaro has wanted a dog for a long time but she and her family live in a building with a No Pets rule and she knows better than to ask. Finally, the Mangiaros move into a new building that allows pets, but now Kelly`s parents don`t want a dog for fear that it will dirty the new furniture. One day while walking in the woods, Kelly meets a mushamute, an interplanetary visitor that looks just like a dog. Will her parents allow her to keep the mushamute? Maybe they will when they see how well Mush prepares a dinner of roast duck with all the trimmings.