Throughout the trial and various court rulings, press attention has focused relentlessly on the personality, movements and motives of Knox, or "Foxy Knoxy" as she has been dubbed.

Director Winterbottom said he wanted The Face of an Angel to bring the focus of the case back to the victim.

"The Kercher family had talked a lot about that, with a huge amount of dignity, the reasons they went for the trial was to make sure that amongst the chaos, it was remembered that someone had lost their life," he said. "That was one of the central things I thought about."

The film is dedicated to the memory of Kercher and comes with the blessing of her family, including her brother Lyle who has watched it.

But Knox's lawyers have threatened to take legal action if the drama is "damaging to her image".

"If the film is based even loosely on the murder in Perugia and if it is damaging to Amanda’s image, we will be asking for damages, as we have done in other cases," Knox’s lawyer Luciano Ghirga declared last year.

Watch Cara Delevingne's big-screen debut in new Amanda Knox thriller