Summer school, what a bummer! That is what Mason, Aidan, Maddie, Melinda and Luke are thinking on the first day of school. Bored, the five of them are daydreaming about what they might be doing if they weren't in school. But when a cute little stray pup they name Chewy wanders into their school, the days are anything but boring. The four of them must unite to help keep Chewy out sight of the principal, Ms. Thistle. What ensues is an elaborate game of hide- and-seek as they not only try to keep Chewy from being discovered, but also clean up the messes he leaves behind. The kids come up with one creative hiding place after another, even enlisting the help of school staff members to keep Chewy's presence under wraps. This game of hide-and-seek can't last forever, or can it? Or will Ms. Thistle catch on to their little secret, and capture them red handed in possession of The Stray?