Controversy Over Whales in Captivity Ignites as "Blackfish" Hits Theaters Nationwide [VIDEO]

Some three years after SeaWorld trainer Dawn Brancheau drowned after the orca Tilikum grabbed her by her hair and dragged her into a deep pool, a conversation over the ethics behind whales in the captive has erupted as the documentary about the event, called "Blackfish," hits theaters nationwide.

First premiered at Sundance Film Festival in January, the movie was picked up by the company Magnolia Pictures for wider release even as the book "Death at SeaWorld" by David Kirby was released in paperback. Together, the two tell a story of intelligent animals that, while often friendly to humans, nevertheless carry with them what some argue is inevitable psychological damage due to captivity.

At the time of Brancheau's death, SeaWorld said Tilikum -- or Tilly -- was playing and that the death was an accident -- a stance it still holds today. However, some are less convinced.

Richard Ellis, a marine conservationist at the American Museum of Natural History, argues that whales like Tilly are too smart to have been acting out of sheer impulse in cases like the one that led to the trainer's death.

"This was not an insane, uncontrollable act," Ellis told the Associated Press. "This was premeditated."

Graham Worthy, a whale expert at the University of Central Florida, said whether the animal meant for the trainer to die is dubious.

"These are animals that can tear apart a blue whale," he told The New York Times. "If this was an animal that was trying to be aggressive, what would have happened would be much more gruesome."

However, there are Tilly's past grievances to take into consideration as well. In 1991, he and two female killer whales drowned a trainer, Keltie Byrne, at an aquarium in Canada during a show. Then, eight years later, SeaWorld officials uncovered a naked body of a homeless man who had sneaked into the animal's pool.

According to the Miami Herald, there was at least one person who had a sense of what was around the corner.

In 2007, Fort Lauderdale dolphin trainer Russ Rector said he wrote SeaWorld warning it was working its show animals too hard in an effort to wow audiences. Doing so, he said, put trainers at risk.

"I warned them this was going to happen," Rector said. "Happy animals don't kill their trainers."