Tapper Watson is an ordinary Erisian boy who loves adventure stories. When his uncle sends him away on a space submarine to other worlds, he just wants to go home again. On an unscheduled visit to Earth, he meets Fern Shakespeare and a talking plant called Morse, and their real-life adventures begin. But chased through worlds by a pair of trigger-happy lobster mobsters in search of the mysterious Nemo Machine, Tapper begins to realise that he might not be so ordinary after all?