>> reporter: just minutes later, their amazing american adventure came to a sudden and tragic end. >> where is he bleeding from? >> everywhere. >> it was horrific. >> no one ever knew that someone would die over it, you know? >> it was just the worst thing that could have ever happened to us. >> reporter: it all began so differently for diren dede. a dream come true. he was an exchange student from hamburg, germany, excited to soak up anything and everything american. at 17 diren had landed in a special corner of the west, missoula, montana. >> he was really charismatic. >> reporter: dana, anna, and chance were three of diren's closest friends at big sky high school. >> he was way different than all of the other foreign exchange students that usually come. he was really outspoken and outgoing, and he just jumped right into the culture. >> he wanted to do everything