A Tale of Three Gunmen

On a late April day in 1999, Eric Harris and Dylan Kleiborn walked into Columbine High School and killed 12 of their classmates. On a late April day in 2007, college student Seung-Hui Cho killed 32 of his classmates.

In 2009, two radically different books addressing these mass-killings were released, David Cullen's "Columbine" and Lucinda Roy's "No Right to Remain Silent."