A terrified Newt Pepperell stumbles out of the woods madly rambling about a flying monstrosity that attacked and killed his companions. But when the Hudson River mysteriously reverses its flow, a team of soldiers, a Mohawk Ally and a stout-hearted trapper named Kate take an armed longboat upriver to investigate. As the team patrols the river, they realize that the mad ramblings of Newt Pepperell may not be ramblings, nor madness, after all.