Sofia is 13 years old, and although she lacks for nothing, she feels lonely and misunderstood – by both her peers and her overworked parents. On her birthday, while traveling in the car with her mother, they accidentally hit a stray dog. The girl immediately rushes to help, names it Smartie, and takes it to the vet. It turns out the animal needs treatment and should be taken to a shelter. When her mother vehemently opposes adoption, Sofia decides to act on her own – she sneaks out with the dog.

With the help of a friend and her older brother, she hides from her parents and the shelter staff, who are on her trail. The girl begins posting videos of Smartie online, which quickly gains popularity and becomes an internet star. All this confusion means that Sofia's parents, forced to work together, become closer to each other and rebuild their family bonds.