In Milwaukee, 104 died after drinking contaminated tap water. At Texas A&M;, a tradition turned tragic when a pile of bonfire logs collapsed onto its builders. Thousands of US soldiers expired in known WWII deathtraps–Sherman Tanks. In 1973, 14 men working on a 26-story building died when supports were removed from wet concrete. And in 1993, Denver’s “dream” airport became a nightmare when its baggage-handling system ran amok. Aided by computer graphics, catastrophe footage, and visits to the locations today, MIT scientists, Center for Disease Control experts, WWII vets, bonfire builders, and construction engineers explain these tragedies and measures taken to prevent them in future.