Unspoken or unknown at the time was the fact the whale at Orlando's SeaWorld had killed before, and that the death would touch off finger-pointing and lawsuits. It also would reignite decades-old debates about keeping whales captive and isolated for hours in tiny dark pools rather than allowing them to swim free in the ocean.

The documentary "Blackfish" thoughtfully and methodically examines these issues although without SeaWorld, which repeatedly declined to be interviewed. That tilts the movie in a way that is regrettable but unavoidable and probably predictable.

Director Gabriela Cowperthwaite speaks with many former trainers, employs footage that shows other trainers in danger and traces the history of Tilikum, the orca that took the life of Dawn Brancheau, 40, in early 2010. She died of blunt-force trauma to the head, neck and torso and drowning.

In 1983, when he was roughly 2 years old, Tilikum was plucked from the North Atlantic and taken to SeaLand of the Pacific, a now-closed aquarium east of Victoria, British Columbia. That is where he killed a 24-year-old female trainer before being sold and shipped to SeaWorld where the stage was set for further tragedy.

Most adults and, certainly, children think of SeaWorld as a vacation destination with whales leaping into the air on command and splashing the lucky patrons in the front rows.

But "Blackfish" makes a case that whales mourn their young when separated and do not belong in tiny pools when they should be swimming hundreds of miles a week in open water.