A controversial biopic about the kidnapping and incarceration of the Austrian Natascha Kampusch, who was held for eight years in a basement cell, has been given the green light despite the death of its main architect.

German film-maker Bernd Eichinger had been working on the screenplay for the project at the time of his death in January. Journalist Peter Reichard, who interviewed Kampusch for German television, helped him with the initial drafts.

Natascha Kampusch's story shocked the world in 2006 when she escaped from kidnapper Wolfgang Priklopil, a communications technician, after being held captive for 3,096 days – much of it in a tiny basement room. Most surprising to many was the fact that the young woman, who was taken when she was just 10, appeared to show empathy with her kidnapper.

Following her escape, Kampusch likened the experience to being "a poor chicken in a hen house". But, she added: "I was also spared a lot of things. I did not start smoking or drinking and I did not hang out in bad company."

Eichinger's film will now be developed by Constantin Film, which aims to install a director and complete the screenplay to a short time-frame. Producer Martin Moskowicz said he plans to begin shooting next year.

News of the film emerged at the Cannes film festival, where another movie with links to the Kampusch case is screening. Michael, from director Markus Schleinzer, makes its victim a small boy rather than a girl.

Priklopil killed himself by lying down on a train track, a few hours after Kampusch walked out of his garden gate while he went to answer a phone call (she had been increasingly allowed her freedom as she approached adulthood). Since then, she has worked as a chat-show host and written a memoir entitled 3,096 Days about her experiences.

Eichinger, who was 61 when he died, was best known as the producer on the Resident Evil and Fantastic Four films, along with the Oscar-nominated German drama The Baader Meinhof Complex. In June it was reported that he wanted Kate Winslet to play Kampusch, despite the fact that the British actor is now 35.