Abbott and Costello are running a pet shop, and Lou brings in a dog. Costello waits on customers. Mrs. Niles brings in a dog for Abbott and Costello to take care of. Lou goes to get a license for the dog. Lou shows up at the marriage license area. He loses the dog. Abbott and Costello go looking for the dog. They search for the dog in a deserted house. They find the dog with Ken Niles.