For decades, Dick Conant paddled the rivers of America, covering thousands of miles along the Mississippi, Yellowstone, Ohio, Hudson, and innumerable smaller tributaries. These solo excursions were epic feats of planning, perseverance, and physical courage. At the same time, Conant collected people wherever he went, creating a vast network of friends and acquaintances who would forever remember this brilliant and charming man even after a single meeting.

Ben McGrath, a staff writer at The New Yorker, was one of those people. In 2016 he met Conant by chance just north of New York City as Conant paddled down the Hudson, headed for Florida. McGrath wrote a widely read article about their encounter, and when Conant's canoe washed up a few months later, without any sign of his body, McGrath set out to find the people whose lives Conant had touched--to capture a remarkable life lived far outside the staid confines of modern existence. Riverman is a moving portrait of a man who was as troubled as he was charismatic, who traveled alone but thrived on connection and brought countless people together in his wake. In the tradition of nonfiction classics like Great Plains and Blue Highways, it is also a portrait of an America we rarely see: a nation of unconventional characters, small river towns, and long-forgotten waterways.