Synopsis

Finn, a small but scrappy teenage muskrat, is frolicking far out in New York Harbor when a terrible storm slams through. The storm finally subsides, and the half-drowned Finn swims home to find den swept away, family gone, and the coastline in ruin. Finn concludes that the family must have relocated away from the open water on the nearby Gowanus Canal, and resolves to go and find them. However, before setting off, Finn is presented with a dilemma in the form of another possible orphan, a baby mouse hiding in a ship container, weeping and squeaking for help. Enter Niblet.

Finn reluctantly takes on this tiny companion, and together they form an unlikely team as they embark on a quest to find their families. The journey up the Gowanus Canal brings them face to face with new friends and foes. They encounter oil slicks, toxins and trash, wily and sometimes helpful creatures, Revolutionary War ghosts and the hideous Sludge Monster.

Ultimately, they find their communities and there is great rejoicing. However, after basking in warmth and security, Finn and Niblet realize that they both have changed. Aside from a deep bond, they have developed a love of learning and a thirst for adventure that compels them to keep moving. Armed with newly forged skills, bravery, plenty of curiosity, and maybe just a little bit of mischief, they set out on their next adventure. Thus ends the first book of the series.