• 'Based on a True Story' shown out of competition at Cannes
• Polanski compares it to his early films
• Eva Green takes rare French-speaking role

CANNES: Roman Polanski, whose 1960s films 'Repulsion' and 'Rosemary's Baby' focused on women in mental torment, returns to the same theme in a film that screened at Cannes on Saturday to mixed reviews. 'Based on a True Story' stars Polanski's wife Emmanuelle Seigner as Delphine, a successful author who makes friends with an overly-keen fan Elle, played by Eva Green, in a relationship that quickly takes on elements of 'Single White Female'. The French-Polish Polanski is still unable to make films in the United States since fleeing the country in 1978 due to fears that a plea bargain with prosecutors over his sexual assault of a 13-year-old girl would be overruled. But he has continued to have a successful career and remains active at 83, securing a premiere for 'Based on a True Story' in an out-of-competition slot at Cannes. 'I have never made a film where there are two principal female characters – it's always a man and a woman, or two men,' Polanski told a news conference of his French-language movie. 'Here two women oppose each other. It's fascinating. There are elements that I dealt with in my first films and I was interested to come back to that type of cinema.' Polanski cast Eva Green - who is French but made her career in English-speaking movies, including in the 2006 James Bond film 'Casino Royal' - as a character who switches from best friend to violent stalker and back and could ultimately be a figment of Delphine's imagination. 'You are always asking, does she exist? Doesn’t she exist? And that is a real challenge for an actor - to try to put some flesh on that character,' Green said. 'Is she a ghost? That's the question.' The Hollywood Reporter's Deborah Young praised 'Based on a True Story' as 'a masterfully made psychological thriller in the traditional mode', but Nathalie Simon in Le Figaro called it 'grotesque, predictable and funny - not a good sign for a thriller'.