Investigative reporter Dave Cullen spent ten years researching and compiling the definitive narrative of the April 20, 1999 massacre at Columbine High. In Columbine, Cullen focuses not only on the events that transpired that day but also what led to Eric Harris and Dylan Klebold deciding to inflict a deadly attack on their peers and teachers.

We live in an age where we’ve become almost numb to mass shootings. While there are outliers like Virginia Tech, Parkland, and Sandy Hook that have captured the attention of the world, there are still dozens every year (there were 34 in the United States last year alone) that escape the kind of public attention that Columbine garnered.

While Columbine was far from the first – University of Texas tower shooting in 1966 and the École Polytechnique massacre in 1989 come to mind – it was the first one that I have clear memories of (I was not exactly around in 1966 and I was five years old in ’89). I was fifteen at the time of Columbine and I remember watching the live television coverage in my classroom as the students fled the school for safety. Before 9/11, it was the single biggest news story that had had a deep impact on me.

In today’s world of constant, unverifiable news coming through kneejerk tweets, Facebook posts and comments on Reddit, it’s worth noting that there hasn’t always been much of a filter imposed on breaking news coverage. Over the years, there have been circumstances surrounding the killings that have seemingly become facts. For example, the two shooters were reportedly part of a deadly cult named The Trench Coat Mafia or that they were exclusively targeting “jocks” and “popular kids” with the belief they had been ostracized by their peers for being “losers”. They were said to be outcasts that loved Marilyn Manson, violent movies and video games and that these things influenced the pair to go on a shooting spree. These were all things that the public and media alike latched onto because it was easier to believe these things rather than the truth: that Eric and Dylan wanted to kill humans for no other reason than that they could and wanted to. And that is the scary part.

Cullen’s research is exhaustive. Aside from the killers, Cullen covers the victims – both the dead and seriously injured – as well as the families who were deeply affected and the battle for meaningful change in the face of an atrocity. The author examines flawed gun laws, the fight to “take back the school” from being a tragedy to a place of pride for the student body and educators alike as well as looking at the lingering effects of PTSD.

There were more than a few completely insane moments uncovered here, the biggest being the incompetency of the Jeffco County Police and the lazy attempt at a cover up when it was discovered that authorities were aware of Eric Harris’ violent tendencies. There was also the fight for financial compensation amongst the injured in the face of financial ruin from medical bills.

Columbine was an event that shattered the lives of so many people and sadly, was not an agent for change. We would come to see this happen over and over again, with even deadlier results. As someone who wanted to learn more about the events of April 20, 1999, Dave Cullen’s journalistic masterpiece provided more than I could have ever expected.