jay bostrom: i'm trying to imagine, did he go to a party and get shot by another kid?issoula and got in a scuffle? i didn't understand it. josh mankiewicz: so what did happen? police on the scene quickly concluded only one person was shot-- the intruder mentioned in that 911 call. 911 dispatcher (on phone): who got shot? caller: (on phone): the robber. he's badly injured. 911 dispatcher: ok. so they entered your garage, and who shot him? caller: my husband. josh mankiewicz: and cops quickly learned something those who thought they knew diren well could scarcely imagine. diren wasn't a random, innocent victim. the young exchange student was the apparent opposite. he was the burglar. just like, someone's trying to break into your car right now. josh mankiewicz: police were about to hear a story from the man holding the gun that night-- a story of terror and a family under siege. markus: and we've been sketched out. we don't feel safe. i'm on edge about everything. two frightened homeowners victimized two times before. what had happened inside that garage? coming up-- mar