Transcript for How Did This Sleepwalker Survive Falling Off a Cliff?
You're about to meet a man who was right on the edge of survive var. Literally. He walked straight off a cliff while sleepwalking. A condition he didn't even know he had. Could it happen to you? Here's ABC's gio Benitez. Reporter: Late night in Kentucky's red river gorge, a frantic 911 call. All search and rescue. We have a fall with a 27-year-old. Reporter: Ryan Campbell out camping with his buddies. The last thing I remember is getting in my hammock and going to sleep. Reporter: Campbell got up from that hammock, walking just steps to a 60-foot cliff and falling off. His friend watched it all unfold. He just saw me take a step and disappear. Reporter: Amazingly, Campbell landing on shrubbery. No slif-threatening injuries. Here's what as really scary. Campbell never realized he had a sleepwalking problem. Obviously, the sleepwalking thing, I didn't see that coming. I sleepwalked fwhu ed once in my adult life other than that. Reporter: Sleepwalking has been fodder. How long has this been going on? I don't think it's that serious. Reporter: Like in "Sleepwalk with me" where he falls for the olympic gold medal of his dreams. Thank you! Reporter: In the 2008 hit comedy "Step brothers," they sleepwalk their way from Christmas eve. I'm walking them up. No, don't wake them up. Reporter: In waking reality, estimates are that more than 8 million Americans sleepwalk. But many of us don't even know we're doing it. Just last October. This woman in Boston sleepwalking right onto subway tracks. Others quickly rushing to pull her out. How can something like this happen? Sleep deprivation. Our country, we don't get enough sleep. Reporter: As for Ryan Campbell, he says he'll keep camping, but from now on, will watch his step. I don't care how rare it is, I'm not sleeping by cliffs anymore. Reporter: For gio Benitez in New York.
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