Two young women attending college decide to have a summer adventure canoeing the rapids-strewn Thelon River that runs 450 miles through the uninhabited Barren Lands of subarctic Canada. Holly made the trip once before with a group of skilled paddlers she trained with at camp, and she wants to share that experience with her friend and lover, Lee, believing it will draw them closer. But a week in, Holly, the risk-taker, falls while taking a selfie near the edge of a cliff. She is left injured and comatose, and soon dies. Their locator beacon for summoning rescue was smashed in Holly's fall. It remains to Lee, the inexperienced paddler, to continue the grueling and dangerous trip alone, to save herself and return her lover's body to civilization and Holly's family.

In their relationship, Holly and Lee had always told each other stories; Lee had called Holly a "storyist." Storytelling helps Lee endure the rigors of her journey and engage her grief as she explores her relationship with Holly while chronicling her own coming-of-age off the grid in Nebraska with her estranged eco-anarchist father, who is now serving time in prison.