Quadruple amputee Daniel Ennett swims with the sharks

Daniel Ennett was floating, suspended far below the surface of the open ocean, when the hammerhead shark started circling.

Ennett completed the daring feat in shark-infested waters of the Florida Keys, without the benefit of a diving cage.

Or arms and legs.

Ennett is a quadruple amputee.

"I tried the cage,"Ennettsaid in the new documentary by Open Sky Pictures. "It was awkward. I figured, if the cameramen were in open water, then I should be, too.

"If they're risking life and limb, then I'm only risking my life."

The Edmonton man swam with the sharks as part of a new documentary, Invincible: Beneath the Surface, which premieres at the Edmonton International Film Festival on Saturday.

Unfolding over six short chapters, Beneath the Surface follows Ennettas he pursues his quest for open dive certification, and travels to Florida to explore the open waters for the very first time.

• Quadruple amputee Daniel Ennett hosts own adventure TV show

"The guy who ran the boat was very whimsical. He's done it a lot, so it wasn't a big deal for him. But going in as someone new, it had an air of danger, despite what the experts will tell you."

The documentary short is the latest installment of the Invincible series, which highlights the achievements of disabled men and women in Edmonton.

'We did the craziest thing we could'

As host of the show, Ennett who lost his limbs to meningitis at five years old has piloted a sailboat, zipped down waterslides, and hit the slopes for downhill skiing.

Show producer Frederick Kroetsch saidthose impressive feats weren'tenough to satisfy Ennett.

"Daniel was sick of being inspiring for doing this or that, and he was like, 'We should do something really crazy, and then I'll actually feel like I'm worthy of being called an inspiration.'So we did the craziest thing we could, and it wasn't easy. But we did it."

'You're in the moment'

More than the dangerous beasts that lurked in the waters, it was the logistical challenges that struck fear into the hearts of the filmmakers.

Getting Ennett's power wheelchair on the plane was a problem, and finding accessible hotels on short notice was difficult.

Forgotten equipment, failing cameras, and bouts of seasickness plagued the crew.

Even in the final moments before he plunged into the water, Ennett was unsure if he could go under. You need to plug your nose to maintain equilibrium under water, so they had to rig a special adaptor inside hismaskbefore he took the plunge.

In the end, swimming with the sharks was nothing short of stunning. And when the hammerhead appeared, hungry for the scraps of raw meat they had dropped in the water, Ennett wasn't afraid.

"It's very serene. I was being dragged along by a couple of dive masters I had with me. So, in that respect it was very easy on my part.

"There were sharks in the general vicinity, which added a bit of tension."

"But at that point, you're in the moment, you want to interact with the creatures. It's a kind of excitement that kind of levels you out."