While traveling with Rohan refugees to Helm's Deep in The Two Towers, Aragorn and his company are attacked by a group of Warg-riding orcs. A battle ensues in which Aragorn is dragged off the edge of a cliff by an enemy's Warg. He is presumed dead, leaving his comrades without their de facto leader. Luckily, Aragorn is found floating down a river and rescued by the horse Brego.

For the river portion of this sequence, Viggo Mortensen did, in fact, float down the river in costume. Unfortunately, Mortensen got caught in an undertow and the weight of his armor dragged him underwater. The actor nearly drowned, but the footage turned out fantastic. As with many takes where actors suffered injuries in Lord of the Rings, Peter Jackson used this near-fatal moment in the final cut of the film.
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