so he let the cafeteria worker go to alert the rest of the school. >> and so then it became just me and michael in the office again. i was terrified on the inside. i know that if i kept him there with me, it was a likelihood that no other one would actually get hurt. >> i called miss tuff. i said, miss tuff, tell me what's going on. she said, everything is fine. we are having a great day here. have a good day. i knew at that point the threat was in the building. >> as police started mobilizing outside the school, inside hill forced antoinette tuff to call 911. >> stop all movement on the ground. stop all movement on the ground. >> you are talking to the shooter? >> he's telling me to tell them on the radio. >> a call that would be her life line. he said he don't care if he die. he don't have nothing to live for. and he said he's not mentally stable. >> on the 911 call, you do sound remarkably calm.