The 'first' mass shooting

Photo: The Canadian Press

In this 1966 file photo, a victim of Charles Whitman is carried across the campus to a waiting ambulance in Austin.

When Charles Whitman climbed to the observation deck of the University of Texas clock tower and opened fire, the first "mass shooting" in modern American history had begun.

But no one called it that because it was a concept that hadn't before been conceived of.

The new documentary "Tower" captures a sense of confusion and carnage that permeates many major acts of violence. But it also illustrates the then unprecedented nature of the attack — in contrast to massacres that have become chilling commonplace today.

"Tower" has begun opening in theatres across the US.

Rather than focusing on the sniper and his acts, though, it explores life on-the-ground during his rampage. The documentary profiles would-be targets scrambling for cover and gunshot victims who survived.