When a mysterious letter written in code arrives at King's house for his human, Kayla, he follows the trail of the person who left it.

Kayla places her tooth in a Tooth Fairy pillow, but it disappears before the Tooth Fairy has a chance to visit. Can her dog King help Kayla find the missing tooth?

Buddy the dog risks everything when he leaves his new family to investigate what happened to Kayla and her father, his beloved former owners, by slipping into a van Kayla's uncle is using to empty her house in the middle of the night.

While searching for his mysteriously lost human family, Buddy the dog is adopted by another family and helps solve the mystery of their missing boy.