Female killer whales are often tamed and can be trained to do tricks for audiences in marine shows, like in . Sometimes, killer whales have even starred in movies, such as the movie titled "Free Willy". Orcas can be dangerous, and have been known to kill their attendants on rare occasions. Some marine parks now require trainers to stay outside the pool when they work with orcas. Unlike wild killer whales, captive killer whales are reported to have made nearly two dozen attacks on humans since the 1970s, some of which have been fatal.