On the way to school, Amorangi realises he forgot to bring an old object to school to talk about. Quickly, he and his sister, Millie, decide to travel back in time and find something. They've travelled back before, after all. He pulls a piece of bark from a nearby rimu and pockets it to ensure they return then they jump back in time. Then begins an adventure that they nearly don't make it back from as one of their ancestors dies, and Amorangi and Millie find themselves fading away. In their travels, the children experience aspects of events in New Zealand history, such as the Taranaki wars, the Tarawera eruption, the Wahine disaster and quarantine on Matiu/Somes Island, and theattitudes of people and the way people lived.