teenager. cnn s polo sandoval has the story. it is a powerful moment. that student planned to take his own life. and he may have done just that had it not been for a quick thinking coach. how the managed to de-escalate the situation. reporter: angel diaz walked into his high school in may with a shotgun loaded with a single shell. this surveillance video shows what happened next. that s keenan lowe encountering diaz at the entrance to a classroom. he grabs the gun with one hand and reaches for the crisis-stricken 19-year-old with the other. what follows was a consoling hug and a conversation allowing police time to respond and take control. coach lowe has kept a relatively low profile for the last five months only discussing that moment publicly a few times including this interview gma.