Grandpa's childhood friend Granddad Gilbert comes to visit with his granddaughter Martha. Unfortunately, Gilbert has forgotten how to have fun so Grandpa sets out to remind him. Mr Mentor the Inventor ...

Great Aunt Loretta asks Mr Hackit to tidy her garden, but Grandpa and Jason like it just the way it is and decide to stop him doing any work. Miss Smiley takes Jason and Troy to Mr Whoop's toy shop, ...

Only seven-year-old Jason knows about his Grandpa's magic cap. When he puts the cap on Grandpa shrinks and creates comic mayhem, but somehow Grandpa and Jason always manage to save the day. It's ...