Boy has planned a perfect sleepover with best friend Tuck that will feature bobblehead-themed activities. However, Boy gets jealous when Tuck keeps getting distracted by his siblings' antics.

Gramps is going to visit his old friend Zeus at their favourite childhood theme park, and the gang tags along for the ride. However, while getting there is half the fun, the kids' antics cause the van to break down! Can they work together to get Gramps to his friend before the park closes forever?