Sharkwater Extinction finished by Windsor professor after Rob Stewart's death

Documentary filmmaker Rob Stewart loved sharks, and he died for it. When he was making Sharkwater Extinction, which will air at Toronto International Film Festival (TIFF) in September, he died during a dive.

To finish his last film that would document his final days on earth, Windsor professor and film editor Nick Hector stepped in.

"I've been making film for thirty years, and this was unparalleled in terms of the number of challenges," Hector said. He is also a professor at the University of Windsor.

Hector said they had to find the story within the 250 hours worth of raw footage left by the late Stewart because a documentary film has no screenplay,

But the filmmaker left the production team with a gift, he said.

They were able to access his diaries and emails and learn about what Stewart liked to see in film the structure, style, sound effects and music that he preferred to finish the film.

"Everybody on board loved Rob and cared about him and really passionately pursued his goal, the idea that we are finishing Rob's work," said Hector.

"We honoured Rob's legacy, we completed his goal, we made Rob's film for him."

The film will explore the final days of sharks traded underground, many of them for their fins.

The demise of these animals are unaccounted for and Stewart wanted to find out where they were being taken to their death.

Stewart's prequel to Sharkwater Extinction, Sharkwater, premiered in 2006. It examined global shark-hunting and the impact on the ocean's ecosystem.

The film premiered at TIFF and has won more than 40 awards at film festivals globally.

Stewart was 37 when he died. Born and raised in Toronto, he headed to Western University in London, Ont. for his bachelor's degree in biology.

Sharkwater Extinction will be shown for the first time Sept. 7 at TIFF.