Josh is so forgetful he almost forgets to put his trousers on when he goes to school on Tuesday. Luckily his magic backpack zooms him into class just as they are discussing the ingredients for a chocolate cake they are going to make. Eggs come from hens, butter comes from cows, and flour comes from wheat, and Josh knows that chocolate comes from cocoa, because his uncle has a cocoa plantation in Africa. Josh offers to bring the cocoa for the cake, but he forgets! Luckily he doesn't forget his magic backpack and before he knows it, he and his friend Tracy are swooshing off - over the sea, over the desert, to the rainforest of his uncle's cocoa plantation. Will Josh get back in time to add the cocoa to the cake?