wrong. watch again. this is the ringling brothers legends show in providence, rhode island, on sunday. just as the curtain drops, 4,000 people in the audience would see this happen. those eight women falling more than three stories. the giant contraption that held them aloft crashing on top of them. the crane was heavy because it took ten guys you could see them struggling to lift it from off top of the girls. reporter: watching this closeup as the cable breaks free. investigators have zeroed in on the metal piece called a carabiner holding the apparatus up. the carabiner failed. it was a single piece of equipment that failed. reporter: remember, these performers are working without a net. watch this rehearsal video. ten rotations in five seconds. experts say a head of human hair is strong enough to support 12 tons. nobody saw a net under the performers.