By Keily Oakes
BBC News entertainment reporter
Ethiopian-born model Liya Kebede plays Waris Dirie
Desert Flower, which has premiered at the Venice Film Festival, tells the incredible journey of Waris Dirie, the model-turned-campaigner against female genital mutilation.
Although Dirie's story is full of drama - fleeing an arranged marriage at the age of 13 and eventually finding herself in London - it is the revelation that she was circumcised as a very young girl that gives the film its emotional centre.
While based on her autobiography, the movie has taken a degree of artistic licence, becoming a strange blend of drama and comedy, with star turns from Sally Hawkins, Timothy Spall and Juliet Stevenson.
But the central message is harrowing. It is difficult to absorb that female circumcision is a practice that continues in great numbers in Africa, and around the rest of the world.
Sir Elton 'sent packing'
Dirie, who is helping to promote the film, is undoubtedly a strong woman, but also confrontational and untrusting in most things she does.
Director and screenwriter Sherry Hormann had the difficult task of persuading her that she would do her story justice.
Sir Elton John had already been sent packing with a flea in his ear after buying the rights to her story and sending along a screenwriter, to whom Dirie took an instant dislike.
With Hormann sitting next to her in Venice, Dirie does not hold back with her first reaction to seeing the film.
"This woman destroyed me," she says.
"When I had finished watching the movie I felt disturbed, I felt sad, angry, I felt really sick to my stomach. I had to run away to the desert for two weeks. It was the only way that could bring me back to sanity."
But she adds: "The movie was what I expected, to have the message, and if no-one can feel this movie I don't know what will move the hearts of the world".
Hormann interjects: "Waris originally said, 'you have to make me a promise, I do not want a solely political, female genital mutilation movie. I want to be entertained, I want young kids to see this movie and to laugh and to cry and to be entertained'.
"And I thought that was the most difficult thing she was asking me, to get that balance between drama and comedy. This is why it took so long.
The actress cast to play Waris Dirie is Ethiopian-born model Liya Kebede, who is now based in the US.
This is her first lead role, having previously appeared on screen in The Good Shepherd and Lord of War.
While Dirie is a confrontational character with an unforgiving harsh manner, Kebede is sweet and gently spoken.
Speaking about the film's central message, she says: "The thing is, I grew up in Ethiopia and female cutting happens in Ethiopia - so you know a bit, but it wasn't close to me and you cannot understand it unless you have experienced it.
"So when I read the book it opened my eyes to what it is for a little girl to go through the process and live with it for the rest of her life."
A mother of two, Kebede does her own campaigning on maternal health, and has started a foundation to tackle the many thousands of needless deaths through childbirth around world because of a lack of access to basic medicine.
Kebede had encountered Dirie once at a party years before the film went into production, but her first official meeting came as shooting ended.
"I felt really awkward because I knew so much about her," she confesses, "but we bonded really well and now we have a great admiration for each other and an incredible connection."
The scene where the young Waris is circumcised is key to the film - but also extremely difficult to watch.
The film shows Dirie's campaign at the United Nations
For Hormann, creating the right atmosphere was important.
"It was not about doing a documentary, it was about creating a feeling," she says.
"I did a lot of research on that, because one of our promises was that this has to be the essential scene in the movie, because this is where it is all heading to."
Dirie made a powerful speech to the United Nations as she began her campaign to highlight the brutality of female genital mutilation. But she quickly fell out with the organisation, getting frustrated with its sheer size and lack of pressure on female issues.
So it was left to Hormann to give advice on what the average person can do build awareness of the problem.
"Look to your neighbourhoods, because immigrants carry the tradition. We don't live in Africa, we live in Europe. I live in Berlin and it happens in Berlin. Try and find out if they are carrying out that tradition.
"In New York City 40,000 girls a year are mutilated. I think if you get a feeling it is happening, just talk to them or call the police."