A documentary by Gabriela Cowperthwaite. Unrated. Opens Friday, August 2, at the Vancity Theatre

Even if places like SeaWorld didn’t “own” orcas with a propensity for killing their trainers, the idea of keeping such noble and intelligent animals penned up for the amusement of passing crowds should make us want to throw up.

Oh, but it’s far, far worse, as documented in this calmly relentless exposé of the killer-whales-for-profit scam, starting with the abusive treatment of Tilikum, a five-tonne bull orca that appears to have killed three people in 20 years.

The trouble started in sleepy Oak Bay, B.C., where the recently kidnapped cetacean, along with two others, dragged a trainer to her drowning death before a horrified audience at the soon-defunct Sea­land of the Pacific. That was a two-bit, cowboy-style outfit compared with the well-oiled machinery of SeaWorld, busy filling its main money pits in Orlando and San Diego. That company bought the killer whale and put it to work without any warning to employees, as attested to by a coterie of former trainers, who gradually went from eagerly parroting the company’s antiscientific propaganda (as seen in archival footage) to whistle-blowing on the horror shows they were part of.

Also aboard is the intriguingly laconic Dave Duffus, an orca expert who testified in several cases against SeaWorld, which obfuscated many facts about the intensely social creatures and about its connections to other sea circuses where trainers were killed or injured. (We’re talking 70 incidents in the past three decades.) The bastards, who for some reason refused to speak to Blackfish director Gabriela Cowperthwaite’s cameras, also specialize in blaming the trainer in every case they couldn’t simply hush up from the start.

The reason for keeping these fatal attractions open? Money, of course. Tilikum produces lucrative sperm. Fully half the whales who “entertain” us are now related to this rebel without applause.