Evan Long - ''The Columbine Cause: An Examination of the April 20, 1999 Attack on Columbine High School'' 88 minutes, color.
How many shots? How many shooters? Was it really a surprise?
Many witnesses to the attack reported other Columbine High School students in the trench coat group with Harris and Klebold as shooters. They even named them: Chris Morris, Robert Perry and others. Several named an adult as a shooter in the science halls while police mysteriously waited for hours to enter the school.
Based on the now-public domain government files related to the official ''investigation'' of the crime.