Billy's not like the other kids. He's a bit moody, a bit cranky, a bit . . . grumpy. In hopes of cheering him up, his mom takes him and his sister to the animal rescue one Saturday morning. All the animals are cute and playful, but they're a little too happy for Billy's taste. When Billy wanders into another section of the store, however, he stumbles across a different group of animals awaiting adoption. These pets are grouchy and scruffy. In fact, they seem downright grumpy - just like Billy! He catches the eye of a particularly grumpy pup - could this be the friend Billy has been looking for? Grumpy Pets shows that there's a perfect match for everyone, if you stay true to yourself.