Lucy, a photographer, meets up with some friends who share her amateur penchant for river running at Cataract Canyon in Utah. The group consists of two women and three men; Thea was Lucy’s student in a photography seminar, and the duo have carried out many river running expeditions together, Henry is new to the undertaking, and Josh and Russell are both experienced runners, although the dangerous nature of their four-day expedition necessitates very little room for error. When Josh forgets to bring their water thermos, Lucy becomes frustrated. The night before their journey, while the rest of the group camps, Lucy makes the 18-mile journey to the local 24-hour market to buy a water thermos on foot and via hitchhiking. Throughout the trip, she is wary of her safety, and ignores the advances of the man in whose car she hitches a ride. Lucy returns to the group that morning, and they are soon in their boats, easily traversing the first part of their route. At first, their boats — one of which contains the men, with Lucy and Thea occupying the other — are hooked together, but Henry and Thea continuously bicker over ideological differences, especially relating to women’s rights and homosexuality, about which Henry feel suspicious. Thea unhooks the boats, and she and Lucy float to the other side of the river and reminisce about past lovers. Over the next two days, the group continues their journey, and the men continue to make misogynistic remarks. At one point, Thea asks Lucy if she has ever been in love with a woman, to which Lucy confesses that she has, although she admits that she has never had sex with one. On the final day, they approach Satan’s Gut, a segment of the river notorious for its danger and known to have taken the lives of several past river runners. The group pulls to the side, and Lucy begins to question the safety of the rapids, especially given the river’s unusually high water level. The men convince her to continue, and follow behind their boat as a precautionary measure.  The group sets out, but quickly lose control of their boats and are nearly smashed against the rock and debris in Satan’s Gut. Lucy stays afloat by grabbing hold of the water thermos, and eventually reunites with the rest of the group, who have all managed to hold on to one of the boats. The near-death experience leaves Lucy and Thea shaken, whereas Josh and Henry immediately begin to downplay the accident and proclaim their lack of fear during the episode. As they leave Cataract Canyon and return to civilization, Lucy feels a heightened connection to Thea, although she cannot tell if what she is feeling is terror or love.