High-speed, action-packed comedy space adventure for six to eight year olds about Rocket Boy, the speediest delivery boy in the universe. A mysterious parcel arrives at Grandpa Sat's with Doctor Square's name on it. Chrystella says they should ignore it, but Rocket Boy says it might be important so he and Toro set off to deliver it. Convinced the parcel is one of Grandpa Sat's pranks, Square immediately dispatches Trash to send it back. By the time Rocket Boy gets home, the box is mysteriously waiting for him, and so begins a strange game of pass the parcel. Just as Rocket Boy seems to have won, Grandpa thinks he might know what the parcel is and it's not good. Legend has it a box just like it contained nothing less than The Most Terrible Thing in the Universe. Rocketboy and Toro race to retrieve it before Doctor Square unleashes the supposed power within, a quest that takes them to the Zone of Emptiness and the perils of the Great Star Beast Baal Thu Maw.