French director Christophe Ruggia, accused by a top actress of assaulting her when she was an underage teenager, will appear before a judge on Thursday to face possible charges, prosecutors said.
Investigators detained the 55-year-old filmmaker on Tuesday on accusations of sexual assault and harassment of a minor by a person in authority. Under French law such questioning can last up to 48 hours.
The prosecutors' office said a judicial investigation would be opened on Thursday morning.
Adele Haenel, 31, lodged a formal complaint against Ruggia in November after accusing him in an interview that month of sexually harassing her when she was between the ages of 12 and 15.
She accused Ruggia, who directed her in the 2002 movie "The Devils," her first film role, of repeatedly touching and kissing her.
Ruggia at first fiercely denied harassing Haenel on the set of the 2002 movie before asking her to forgive him. He then said that she was targeting him because he denied her a part in another film.
Haenel's accusations stunned the French film industry, which has generally been slower than Hollywood to react to the #MeToo movement that has turned the spotlight on sexual abuse in the sector.
But she won support from some of the top names of French cinema including the actress Marion Cotillard, who hailed Haenel for "breaking a silence that was so heavy."
Haenel, who starred in the period drama "Portrait of a Lady on Fire," one of last year's art house hits, initially said she did not intend to file a complaint, slamming the "contempt with which the judicial system treats women."
But prosecutors opened an investigation of their own accord and Haenel eventually did file a complaint.
Haenel said also that Ruggia's public denials had made her "determined to obtain through judicial means the status of a victim".
In another case to shake the French cultural world, the award-winning essayist Gabriel Matzneff is the subject of a rape investigation after prominent publisher Vanessa Springora published a memoir describing a sexual relationship she had with him while she was still a minor.