The Cavity Goon and Miss Sweety plot to capture Brushbrush in order to bait Timmy and hand him over to the Tooth Fairy.
During a rainy day, Timmy imagines that he is Captain Good Guy, and Brushbrush is his first mate. They work to save Sunny the Sun from The Cavity Goon and Miss Sweety.
Set in Flossmore Valley and Egypt, Timmy, Brushbrush and Bubbles visit the pyramids on their official pyramid investigation business as they explore the pyramid of King Tooth Uncommon.
Convinced his friends forgot his birthday, Timmy visits Mr. Wisdom and is shown what Flossmore Valley would be like if he wasn't around.