Question: Im Not Ashamed is a biographical drama film, based on what massacre involving two American spree killers Eric Harris and Dylan Klebold, who killed 13 people and wounded 24 others? 
Sentence (from "Eric Harris and Dylan Klebold"): Eric David Harris (April 9, 1981 – April 20, 1999) and Dylan Bennet Klebold (September 11, 1981 – April 20, 1999) were two American spree killers and mass murderers who killed 13 people and wounded 24 others armed with firearms and knives on April 20, 1999, at Columbine High School in Columbine, Colorado.
Relevant evidence: Yes