Danish submarine owner and inventor Peter Madsen lands with the help of the Danish defence in Dragor Harbor south of Copenhagen, Denmark August 11, 2017. Scanpix Denmark/Bax Lindhardt/via REUTERS ATTENTION EDITORS - THIS IMAGE WAS PROVIDED BY A THIRD PARTY. DENMARK OUT. NO COMMERCIAL OR EDITORIAL SALES IN DENMARK.

Peter Madsen.

Victorian writer/director Emma Sullivan’s feature documentary centred on the aftermath of the brutal murder of a Swedish journalist will premiere in the world cinema documentary competition at the Sundance Film Festival.

Netflix commissioned Into the Deep from Danish producer Mette Heide, who hired Australian producer Roslyn Walker to work with her on the production. Heide produced Amanda Knox for Netflix, an account of the conviction of the American exchange student and eventual acquittal for the 2007 death of another student in Italy.

Sullivan began shadowing the Danish inventor and rocket engineer Peter Madsen in 2016 for a documentary on his workshop, the interns including physics graduates with whom he worked, and his attempt to become the first amateur astronaut in space.

The film took a shocking turn after Madsen was convicted last year of the 2017 murder of Swedish journalist Kim Wall on board his submarine UC3 Nautilus. He was sentenced to life imprisonment.

“This is a very personal story to me,” Sullivan said. “When I started this project I met a group of young people who wanted to be part of something positive with a mentor they admired at the helm. But then the unbearable happened.

“When you are suddenly pulled into such a nightmare it changes your life forever. The film is a testimony of the young interns as they slowly grasp the true nature of the man and the terrible crime he committed.”

The young people’s testimonies and Sullivan’s recordings helped get Madsen convicted, according to a Netflix media release.

Film Victoria funded the development of that doc, which means the agency will have two projects it supported at Sundance. Natalie Erika James’ horror movie Relic will have its world premiere in the Midnight section.

Into the Deep will screen on Netflix next year.