The film will tell the salacious story of the final years in the life of Hollywood screen icon Errol Flynn, portrayed by Kevin, and his relationship with teenage actress Beverly Aadland, to be played by Dakota, Deadline reported.
Beverly was 17 when she tended Flynn at his bedside before his death, aged 50, in 1959.
Susan Sarandon has been cast as Florence Aadland, who wrote the 1961 book The Big Love accusing Flynn of starting a sexual relationship with her daughter when Beverly was 15, an allegation Beverly later confirmed to People magazine.
Hollywood heartthrob Flynn, star of The Adventures Of Robin Hood, was the subject of much scandal and gossip.
He was married to actress Patrice Wymore until his death - but began dating South Pacific star Beverly after meeting her at Warner Bros studios in 1957, despite the 33-year age gap. He cast her in his 1959 film Cuban Rebel Girls and also is reported to have campaigned for himself and Beverly to star in Stanley Kubrick's Lolita, about a man who falls in love with his teenage stepdaughter.
Filming is due to begin in February.