>> reporter: it's a dilemma that confronts every teenager. how to simultaneously fit in with your friends and rebel against everyone else. that two-step is made a little easier by the knowledge, maybe the certainty, that you're going to live forever. >> kids do dumb stuff all the time. >> reporter: and so sneaking out of the house in the dead of night to meet other teenagers to drink, party or just hang out, well, that's nothing new. usually teens sneak back home safely. this wasn't one of those times. >> i thought it was some kind of, like, joke. i, like, just couldn't believe it, really. >> i was just freaking out. i was like, "it can't be. it can't be." >> reporter: it was april 2014 when two bright foreign exchange students living in montana slipped out of their home. >> he's lying face down. he's barely breathing. >> reporter: just minutes later, their amazing american adventure came to a sudden and tragic end.