Tom and his sister Lucy are no strangers to adventure. But now they are ready for their biggest challenge yet: teaming up for a joint expedition. Inspired by the great explorers, they set out to retrace an epic journey across America by canoe. Two hundred years ago, Meriwether Lewis and William Clark travelled into the wilderness; now it's Tom and Lucy's turn to paddle mighty rivers, battle wild rapids and camp beneath endless starry skies. Along the way they discover what has changed: technology, the size of towns and cities, and the people who live in them; and what has stayed the same: the physical hardship, the camaraderie and the pure thrill of adventure. Blending action, humour and fascinating historical detail, this unforgettable middle-grade adventure proves that the spirit of exploration is as exciting today as it was two hundred years ago.