Princess Eugenie has hailed as a “hero” a Canadian filmmaker who died in a scuba diving accident while making a documentary about illegal fishing and shark finning.

Eugenie was among celebrity guests including models Pixie Geldof and Cressida Bonas when she attended the UK premiere of Sharkwater Extinction in London on Tuesday night.

The action-packed documentary was made by acclaimed Toronto director and conservationist Rob Stewart, 37, who died while filming off the coast of Florida in January 2017.

“I think it’s going to be amazing,” Eugenie said before the screening at Curzon Soho cinema.

“It’s such a wonderful cause and Rob is such a hero and inspiration.

“So any way we can share his message and the story of these sharks and what the world can do to be a part of it is amazing.”

Sharkwater Extinction Premiere – London
Princess Eugenie said filmmaker Rob Stewart was an ‘inspiration’ as she attended the premiere of Sharkwater Extinction in London (PA/John Stillwell)

The princess, who is an ambassador for global ocean charity Project Zero, met the filmmaker’s mother Sandy Stewart, who finished the documentary with husband Brian after their son’s death.

Mrs Stewart said she was “really, really proud” of her son, who always had a passion for the ocean since he was a boy, convincing his entire family to take up diving by the age of 13.

“Rob did so much for sharks and the oceans. He changed people’s perceptions of sharks around the world,” she said.

“He was the first person to alert the world about shark finning. So he’s changed so much. His films are action-adventure and fun to watch. He really made an impact.”

Sharkwater Extinction Premiere – London
Actress and model Cressida Bonas arrives for the premiere of Sharkwater Extinction at the Curzon Soho cinema (PA/John Stillwell)

Shark Extinction is Stewart’s third film, following his award-winning Sharkwater (2006) and Revolution (2012), and it recounts his crusade across four continents to investigate pirate fishing and the illegal shark finning industry.

Shark fins are used to make shark fin soup and some traditional cures, and Stewart’s film warns the practice is leading to the extinction of the ocean’s oldest predator.

Mrs Stewart, who travelled from Toronto for the premiere, said she and her husband went through 400 hours of their son’s footage to piece the film together.

“Then we hacked into Rob’s iPad, which Apple said you couldn’t do, but we had a clever IT guy,” she added.

“Inside there were scenes, graphics, the exact cinematography he wanted for each scene, the exact messaging he wanted each scene to convey.

“So it was kind of a roadmap. But nevertheless he left 400 hours of footage so it was a big job.”

She said Stewart wanted people to “live in harmony with nature”.

“Conservation is really the preservation of human life on earth,” Mrs Stewart added of her son’s message.

“You can’t save something without saving everything. The oceans matter, and the sharks matter to the oceans.”

Sharkwater Extinction will be released in UK cinemas in February 2019.