LATEST: The British socialite-turned-bounty hunter portrayed by Keira Knightley in DOMINO accidentally overdosed on painkiller fentanyl, according to autopsy reports.

One-time model DOMINO HARVEY, the daughter of film star Laurence Harvey, left the cast and crew of her biopic devastated when she died in mysterious circumstances in June (05).

But now Los Angeles Deputy Medical Examiner RAFFI DJABOURIA has solved the mystery - she overdosed while she was in the bath.

Initial reports suggested Harvey had drowned, but Djabouria insists his findings suggest that didn't play a part in her death.

Insiders claim Harvey, who was under house arrest on drug trafficking charges, was being supervised by "sober guardians" hired by her mother, PAULETTE STONE, to keep the ex-model away from drugs and alcohol when she passed away.

According to the report, one of these guardians was chatting to Harvey minutes before she died - while she was bathing.

When she fell silent and was unresponsive to his questions, he kicked the locked bathroom door down and found his charge dead in the bath.

Harvey acted as a consultant to director Tony Scott, and even sang the gritty film's haunting theme song.