Three different Princess Diana films are lined up after the success of The Iron Lady.
Charlize Theron and Carey Mulligan are allegedly set to battle it out to see who will play Princess Diana in the upcoming £30 million biopic.
Ewan McGregor is likely to play Ken Wharfe, Diana's former bodyguard with Evans keen to tell the world the 'truth' in behind what happened to the late Princess, who would have been 51 this year.
The Oscar-winning South African actress Charlize, 36, is favourite to play the late Princess although because it's set before her divorce from Prince Charles, it's thought that 26-year-old Carey is in with a chance.
The £30million film, out next year, will be told from the point of view of bodyguard Ken Wharfe and is based on his controversial 2007 book Diana: Closely Guarded Secret.
Evans has also been working with Diana’s private secretary Commander Patrick Jephson. The plot will follow the years leading up to Diana’s divorce from Prince Charles in 1996. But it will not cover her relationship with Dodi Fayed or theories about her death in a 1997 car crash. Evans said: “We are dealing with about 11 years of her life from after she had Harry, when he’s aged about two, and it’s partly from the point of view of her protection bodyguard.
“The emphasis of this really is authenticity and to discover what she went through.
“Unless you are a Diana freak, quite a lot of it will be unknown to the audience. The movie’s not saying she is unbelievably wonderful or she’s a pain in the neck, the audience can make their own view.”
Evans would not reveal who is currently favourite to play the princess, saying: “It’s a slightly closed book until we get her.”
Meanwhile, two other Diana biopics are in pre-production.
Scarlett Johansson, 27, and Keira Knightley, 26, are rumoured to appear in a Pathé film called Diana.
And Jessica Chastain, 30, is set to star in Caught in Flight, which details Diana’s relationship with heart surgeon Hasnat Khan.