Becket Branch wants a dog for her tenth birthday. But her twin brother, Nicholas, has secretly been wishing for a cat. Lucky for Becket and Nicholas, their animal-loving parents have an animal-loving surprise for them: they're going to the local shelter and adopting both a cat and a dog. Becket's dream dog, Dibs, turns out to be a super-shy scaredy-pooch who is going to need a lot of training. Meanwhile, Nicholas's cat, Given, is more outgoing and attention-seeking than the just-for-him pet he was expecting.