“When I first saw the dolphin, I thought it could be real,” said a woman who swam with the remote-controlled creature.

Edge Innovations, a U.S. engineering company with an animatronic and special effects division in California, designed the dolphin, which starts at $3 million to $5 million.

It hopes that life-like animatronics used in Hollywood movies could one day entertain crowds at theme parks, instead of wild animals held in captivity. Swimmers could dive with robotic great white sharks or even reptiles that filled Jurassic-era seas millions of years ago.

“There are like 3,000 dolphins currently in captivity being used to generate several billions of dollars just for dolphin experiences. And so there’s obviously an appetite to love and learn about dolphins,” said Edge Innovations founder and CEO Walt Conti.