Eleven-year-old friends Sam and Lucas embark on a quest to find "magical mushrooms", upon overhearing their uncle talk about the psychedelic wonders of the drug of the same name. Venturing through imagined forests and caves, they encounter a series of obstacles including a red-cloaked bogeyman. After finding the mushrooms in all their ethereality, they return home to a surreal twist: bright red toadstools seemingly growing from the floorboards.