Guns? Guns! Be sure to enjoy a gun today! That said, Keith Maitland’s wrenching documentary Tower recreates the very bad day in August 1966 when crew-cutted, 25-year-old Charles Whitman — a former altar boy and Eagle Scout, and lifelong gun enthusiast — climbed to the top of the University of Texas’ Tower with a bag full of rifles, shotguns, and other constitutionally protected firearms and shot 49 people, killing 16. Photographs, news footage, and radio air-checks are intermixed with rotoscope-animated recreations of the survivors telling their stories, first portrayed by actors for their 1966 selves and eventually replaced without animation by the real people as they are today. Most harrowing is the tale of improbable survivor Claire Wilson, who was 8 months pregnant and lost both her baby and her boyfriend that day, spending the 95-minute ordeal bleeding out on hot pavement. In addition to being as close to a you-are-there document of an incident that the NRA would probably rather we forgot, Tower also works as a study of both survivor guilt and guilt-guilt. Many witnesses, out of harm’s way, struggle with the fact that they didn’t risk getting shot to help Claire and the others. The questions raised from a half-century ago are no closer to being answered now — especially, why does this keep happening?