In August 1966, a student and former Marine ascended to the top of the tower that housed the University of Texas' main library and began shooting at people below. He killed 14 people on the campus and wounded 31 more. Hours earlier, Charles Whitman had killed his wife and mother in their homes. He was eventually shot to death by police. A 15th victim died in 2001, from injuries sustained in the attack. Now the new documentary Tower re-creates that 96-minute-long massacre in an original way, using archival film and new interviews with an animated portrayal of the events.