Jason Mason lives with his mum, dad, sister, dog and grandpa in the beautiful seaside town of Sunnysands. Jason and his grandpa have lots of hilarious adventures together when Grandpa puts on his magic shrinking cap. It makes him grow small enough to fit into Jason’s pocket, as well as Jason’s toy cars and planes which Grandpa can bring to life!

When he’s miniature, Grandpa especially likes to be chased by Jason around the house while yelling “Catch me if you can!” Grandpa is playful and mischievous, causing all sorts of mayhem when he shrinks, but despite all the chaos he causes, Grandpa is a force for good. This is because Grandpa can’t bear it when someone is rude, mean or selfish, so sometimes he shrinks to teach someone a lesson. Each story ends with Grandpa saying "We did it, Jason! Teamwork!"