Moving to New York City brings excitement and challenges for Ray, Sal, and Chestnut. Their apartment has a strict No-Pets allowed sign on the front door, and to make matters worse the girl's new Dad (Matt) is allergic to dogs, forcing the girls to keep their secret, Chestnut hidden. Chaos ensues when their housekeeper, Rosamaria, mistakes Chestnut’s antics for a rat infestation, setting off traps he cleverly avoids. Despite the close calls, the sisters manage to keep their secret, even as Chestnut explores his new home.