On April 20, 1999, Eric Harris and Dylan Klebold walked into Columbine High School in Littleton, Colorado. In a matter of minutes, they killed twelve students and a teacher and wounded twenty-four others before taking their own lives.

For the last sixteen years, Sue Klebold, Dylan's mother, has lived with the indescribable grief and shame of that day. How could her child, the promising young man she had loved and raised, be responsible for such horror? And how, as his mother, had she not known something was wrong? Were there subtle signs she had missed? What, if anything, could she have done differently?

Here she chronicles her journey as a mother trying to come to terms with the incomprehensible, shedding light on one of the most pressing issues of our time. In the hope that the insights and understanding she has gained may help other families recognize when a child is in distress, she tells her story in full, drawing upon her personal journals, the videos and writings that Dylan left behind, and on countless interviews with mental health experts.