For decades, marine parks presented killer whales as intelligent, powerful animals that could be trained to perform spectacular tricks. Audiences watched trainers swim beside them, ride on their backs and perform routines that made the enormous animals appear almost completely under control.Behind the performances, however, working with orcas carried enormous risks. These animals are highly intelligent predators weighing thousands of pounds, and no amount of training could completely eliminate their natural instincts or unpredictability.Ken Peters discovered that firsthand during a terrifying performance at SeaWorld San Diego in 2006. The experienced trainer was working with Kasatka, a female orca that had been captured in 1978 when she was only two years old.Kasatka had already developed a reputation for aggressive behavior around humans. She had previously bitten trainers on their legs, thighs and feet, and between 1989 and 1993, there had been three reported attacks involving her, including two involving Peters.Despite that history, Peters continued working with her and had years of experience handling the massive animal. On November 29, 2006, he entered the water with Kasatka as part of a scheduled performance at SeaWorld San Diego.At first, everything appeared completely normal. The routine was underway, the audience was watching, and there was no obvious indication that anything was about to go wrong.Then Kasatka suddenly grabbed Peters by the foot.The approximately 5,000 pound orca pulled him underwater, taking him completely below the surface. Peters was forced to hold his breath as the enormous animal dragged him through the water.After nearly a minute underwater, Kasatka brought him back to the surface. Peters was still alive, and rather than immediately fighting the animal, he attempted to calm her. He gently touched and stroked her, hoping that the familiar interaction would convince her to release him.For a moment, it seemed to work.Then Kasatka dragged him underwater again.Peters was pulled beneath the surface repeatedly while the orca occasionally thrashed him from side to side. Every second underwater brought him closer to losing consciousness, but fighting the animal physically was practically impossible. Kasatka was far too powerful, and any sudden struggle could have made the situation even worse.Other trainers immediately realized that Peters was in serious danger. They rushed to help, throwing a net toward him and using hand signals in an attempt to make Kasatka release him.Nothing worked.Peters continued trying to remain calm while holding his breath. According to accounts of the incident, his decision to gently rub and stroke Kasatka while she held him may have helped prevent the situation from becoming even more violent.Eventually, the orca loosened her grip on his foot.Peters seized the opportunity and escaped toward the other trainers. He was pulled from the water and taken for medical treatment, but remarkably, his injuries were limited to a broken foot.The incident raised questions about what Kasatka had been trying to accomplish. Former trainer Carol Ray later suggested that the orca may have been deliberately making a point by repeatedly holding Peters underwater rather than immediately releasing him.Peters eventually recovered from the attack and continued to defend his decision to work with orcas. Years later, he testified in connection with the death of another SeaWorld trainer, Dawn Brancheau, who was killed by the orca Tilikum in 2010.Despite the danger, Peters maintained that working with the animals was an acceptable risk. His encounter with Kasatka, however, demonstrated just how quickly a routine performance could turn into a fight for survival.In the end, Peters survived because he remained remarkably composed while a 5,000 pound predator repeatedly dragged him beneath the water. Instead of panicking and fighting wildly, he stayed calm, waited for an opening and used the moment Kasatka loosened her grip to escape.