It's Christmastime in Pleasant Valley and the town is getting ready to celebrate. But when all the lockers at the Pleasant Valley swimming pool are emptied during the Big Holiday Swim, it looks like Christmas won't be very merry. Once again, Jerry and Maya use their super sleuthing skills to help the police chief track down the mysterious thief before he ruins Christmas for the whole town.

It is pool day in the city and everyone is welcome.

Henry's friends are excited to try out the diving boards at their new community pool, but Henry's fear of heights dampens his enthusiasm.