Idaho's winter ice is thawing and the people living on the banks of the River of No Return are forced to navigate the potentially fatal spring rapids.

A rancher along the river is threatened by a predatory bear that is stalking the homestead and is forced to aggressively protect himself and his cattle.

A jetboat captain is forced to spring into action as a rafter topples into the murky waters of the river. Then, heavy rain threatens to destroy Aubrey's ranch.

Buck decides it is time for his eight-year-old son Dax to learn how to captain a Jetboat. Meanwhile, rancher Aubrey looks after a pregnant mare during a risky delivery.

Father and son jetboat captains take on Deadman's Rapids; as a storm bears down, scrambling to re-roof the barn, Pete takes a potentially catastrophic fall; felling a massive dead tree puts Ron and Wes at risk from widow makers crashing from above.

With dangerous rocks exposed by low water, Buck must hit high speeds to keep his jetboat out of harm's way; landing solo on a narrow airstrip tests Katie as a pilot; Aubrey plays matchmaker between her reluctant mare and a stud donkey.