Ted Griffin had a vision of himself on the sleek, black-and-white back of an adult orca, zipping through the sea spray along that faint blue line between water and sky.

To Griffin, it was never only a dream — it was a plan. To the rest of the world, it was crazy.

Until Griffin captured and displayed America’s first show orca 50 years ago, the sea creatures were something to be feared, not befriended. “Killer whales” (which are actually a species of dolphin) were respected, even worshiped, by some native cultures, but for the most part they were viewed with deadly dread. Fishermen sometimes shot them because they interfered with their catch. Divers were taught that the whales would viciously attack any human on sight. One ancient Roman observer wrote that the creatures “cannot be properly depicted or described except as an enormous mass of flesh armed with savage teeth.”

Then, in June of 1965, Griffin bought a 22-foot orca from a group of fisherman who had accidentally caught him near British Columbia (it cost him $8,000 and a win in an arm-wrestling contest). He gave the animal a name — “Namu” — a backstory and a host of human qualities, and by the time Griffin finally rode his whale several weeks later, the creatures had become a cause célèbre. Killer whales were now a lovable icon, a conservation imperative and the sudden stars of a spectacle everyone wanted to see.

Half a century later, the world’s most famous keeper of captive killer whales, SeaWorld San Diego, has announced that it will be phasing out “theatrical” stunts like Griffin’s famous first ride. Amid plummeting profits, regulatory challenges, widespread criticism about the treatment of captive whales — not to mention the ethics of keeping them in the first place — and one very effective documentary, the park says it will unveil a new, more natural kind of “orca experience,” one without the antics and acrobatics.

The change does not apply to SeaWorld’s 10 other U.S. parks, but it is perhaps a sign of things to come. American audiences are growing increasingly uncomfortable with animal entertainers, SeaWorld’s splashy shows — plagued by ailing animals and dangerous and sometimes deadly accidents involving human trainers — in particular.

Then again, the writing has been on the wall for 50 years. To understand what’s happening with SeaWorld San Diego’s last performing whales, you don’t have to look any further than what happened to the very first ones captured and displayed by Griffin.

Namu, Griffin’s first captive orca, arrived at the Port of Seattle in July 1965 to unprecedented fanfare, according to Canadian magazine the Tyee. A flotilla of researchers, reporters and anyone else who could get their hands on a boat paddled out alongside the whale’s floating steel cage. Thousands of onlookers lined bridges and docks, cheering as the black-and-white behemoth was towed into the harbor. Namu appeared on the front page of every newspaper in the Pacific Northwest — and many outside it — as well as T-shirts, key chains, mugs and coloring books sold at the Seattle Aquarium, his new home.

Namu wasn’t the first killer whale to be put on display, but he was the first to be put to work in the kind of acrobatics orcas are now known for. Far from the “killers” of legend, orcas are playful, intelligent and unusually amenable to having small, enthusiastic two-legged creatures sitting astride their backs while clutching their dorsal fins. Griffin, Namu’s keeper and trainer, came to see Namu as a “pet,” he said, one that was very nearly human.

“I had loved Namu passionately, perhaps with the same capacity and energy that often exists between women and men,” Griffin said in a memoir about his time with the whale. “I had wanted to spend every minute with my companion.”

Shortly after Namu’s arrival, Griffin set out in search of a finned companion for Namu. In October 1965, he got what he was looking for: a 14-foot female orca he and a colleague were able to trap in a corner of the Puget Sound. They brought her back to Seattle, placed her in Namu’s enclosure and waited for sparks.

They never came. Instead, the female whale became increasingly aggressive toward both Namu and Griffin. When SeaWorld came looking for an orca for its facility in San Diego, Griffin offered them the young female for $70,000, according to Outside magazine.

“They wanted to call the whale Namu, and they wanted the rights to the name, and I wouldn’t do that,” he recalled to PBS.

Instead, the park settled on a portmanteau of “she” and “Namu.” (Apparently they weren’t interested in just giving the whale a name of her own.) Their new attraction would be named Shamu.

“And that’s how it all started,” Griffin concluded.

“It all” was several decades of aggressive whale trapping for theme parks and aquariums around the world, much of it done by Griffin himself. He and colleague Don Goldsberry sold some 30 whales during seven years of hunting, each of which sold for a $20,000 or $25,000, according to the Seattle Times. They may have rounded up as many as 10 times that number; the others escaped or were released.

Or were killed. Of the dozens Griffin captured, 11 orcas died after being tangled in his nets or injured during a chase. Five of the deaths came in one fateful event at Penn Cove, a curve in Washington’s Whidbey Island where Griffin had set up a whale catching operation.

During the 1970 capture, more than 80 whales wound up in Griffin’s net — far more than he wanted. And a few of them died before he could free them. Rather than sell the animals to a rendering plant, as he usually did, Griffin ordered the creatures to be weighted and sunk, hoping to avoid bad press.

But the plan didn’t work. Three of the bodies later washed ashore, their bellies slit and filled with rocks. Newspapers started asking questions, onlookers became outraged. Shortly afterward, Washington state passed legislation banning the capture of orcas in Puget Sound, and two years later, the federal Marine Mammal Protection Act ended almost all other orca captures.

Meanwhile, orcas that had already been captured were surviving with only varying success. Namu, Griffin’s beloved first capture, died within a year of his arrival at the Seattle Aquarium; he fell ill after swimming in the polluted waters of the Puget Sound, Griffin told PBS, and, delirious, got tangled in the netting of his enclosure and drowned.

At SeaWorld in San Diego, Shamu also ran into problems. In her sixth year at the park, Shamu — who had previously been acting erratically — bit a young woman who fell off her back during a training session. According to legal documents, the trainer suffered 18 to 20 wounds requiring as many as 200 stitches. Shamu was taken off the performance circuit, and she died several months later.

Several of the subsequent stars of the park’s shows, all referred to as Shamu in honor of the original orca, have also behaved violently toward trainers. According to David Kirby, author of “Death at SeaWorld,” 15 percent of all orcas at SeaWorld parks have been involved in “acts of serious aggression” against trainers.

The effects of captivity on orcas are still debated. The Humane Society and other animal rights groups argue that the large and social animals fare poorly at aquariums and parks, where they lack companionship and are more susceptible to infection. Wild whales have a longer life expectancy, the group said in a 2011 report, and are less likely to exhibit “aberrant” behavior, including attacks on people. Captive orcas have been implicated in the deaths of at least four people since 1965; there are no records of wild orcas ever killing a human.

But SeaWorld says that its captive whales connect people with nature on a scale that would be impossible if orcas only existed in the wild, and that the money it makes from exhibiting the animals goes back into protecting their habitat and preserving the species.

“SeaWorld … contributes immensely to conservation through its effect on people’s thinking,” Brad Andrews, the park’s Chief Zoological Officer, told PBS. “Conservation [has] to be a group effort, and if the public doesn’t receive the sensitivity, the education, the concern, then how is conservation going to happen?”

A recent study of SeaWorld whales co-authored by researchers from SeaWorld and the Minnesota Zoo found that there is no significant difference between the survival rates of captive and free-ranging whales. That report was commissioned by SeaWorld.

Regardless of the merits of SeaWorld’s arguments, people seem to have drawn their own conclusions. The 2010 killing of a beloved and highly qualified trainer by an orca that had already been involved in two other deaths, a focus of the 2013 documentary “Blackfish,” turned public opinion against the park’s circuslike spectacles. However intelligent, lovable and playful killer whales might be, they’re not “pets,” as Griffin described Namu.

SeaWorld’s profits have plummeted 84 percent since “Blackfish” was released, according to Time.

“We start everything by listening to our guests and evolving our shows to what we’re hearing,” SeaWorld chief executive Joel Manby told the San Diego Union-Tribune, “So far that’s what we’ve been hearing in California. They want experiences that are more natural and experiences that look more natural in the environment.”

As for Griffin, the man who started it all? He says that he wouldn’t take back any of the choices he made — not the orca captures; not the sale of Shamu; not that first, fateful voyage from British Columbia to the Port of Seattle with Namu in tow.

But he doesn’t go near whales anymore, he told PBS in 1997 — the last time he gave a lengthy interview. He doesn’t even go in the water. Like SeaWorld’s, his association with whales has been tainted by decades of bad history.

The closest he gets is in his boat, the orcas’ squeaks, screeches and clicks reverberating against his hull.

“It’s because I know what whales do underwater,” he told PBS. “My boat follows the whales, and I ride with them.”