The second half is gripping. There's less time for talk, and the Smith brothers give us a superb sense of the fearful power of this landscape. Maybe that was the point all along: nature just keeps on giving and taking.

The mountain backdrops are stunning, but the movie's real draw is its understanding of how children pick up more from their parents than their skeptical, self-pitying moms and dads ever imagine.

Walking Out has an effect: Bomer is doing something different and he and Wiggins have believable father-son chemistry; the setting is gorgeous and desolate; and the hero's journey narrative is comfortingly familiar.

The film’s title makes the impending peril obvious, but the buildup of the two main characters and their strained relationship gives form to the danger once it hits.