Oksana Grigorieva with Timothy Dalton in 1997. Credit: WENN.com

Mel Gibson has been married for over 28 to Robyn Moore, but that’s about to change. Robyn has filed for divorce and stands to emerge with the highest known settlement in Hollywood history. Mel and Robyn don’t have a prenuptial agreement and under California law she’s entitled to half his fortune, estimated at nearly a billion USD. Before the divorce became public, the 53 year-old father of seven was photographed out twice with a woman rumored be his mistress, a tall dark haired woman known only as singer named Oksana.

There’s been plenty of speculation over who Gibson’s mystery Oksana could be. Earlier in the week a 24 year-old Russian singer named Oksana Pochepa came forward to claim that she was the Oksana involved in a relationship with Gibson. That seemed to be a publicity stunt as that Oksana had light hair and blue eyes and looked nothing like the dark-haired brown-eyed woman photographed with Mel. Another Oksana, a blonde married piano player, also denied a relationship with Mel.

People Magazine has dug up more on Mel’s mystery Oksana. She is a 39 year-old singer signed to Gibson’s record label and it looks like she’s living in a home he purchased for her. Oksana Grigorieva was previously in a relationship with Timothy Dalton, with whom she has a grown 12 year-old son:

Shortly after Mel Gibson’s wife Robyn filed for divorce last week, details emerged about a woman the actor-filmmaker has been spending a lot of time with – even taking her on a family vacation to Costa Rica – named Oksana. She is, sources tell PEOPLE, a Russian singer signed to Mel Gibson’s record label, Icon Records.

Now the identity of his mystery girlfriend may be revealed: Public records suggest Oksana Grigorieva, 39, an ex of former James Bond star Timothy Dalton, has lived in a house linked to Gibson, 53.

The home, purchased in Sherman Oaks, Calif., in December 2008, has an ownership trust administered by the CFO of Mel Gibson’s production company, Icon.

While neither Grigorieva nor Gibson have commented, Grigorieva certainly resembles the leggy brunette photographed with Gibson on the Boston set of his upcoming film, Edge of Darkness, and seen frolicking in the surf with the star in Costa Rica.

A composer, Grigorieva is dedicated to her craft, her former agent Victor Kruglov tells PEOPLE. “She’ll never give up with her music,” says Kruglov, who has seen photographs of Mel’s mystery woman and believes she and Grigorieva are one and the same. “She loves it.”

Though she rarely confided in him about her love life, Kruglov says Grigorieva did once complain about trouble with a boyfriend – but stopped short of sharing specifics. “She was always very discreet about her personal business,” he adds.

She has one son with the 63-year-old Dalton, Alexander, who is based in Los Angeles.

[From People]

I wonder if this woman was signed to Gibson’s record label before or after they hit the sheets. Now that it’s known that Mel bought her a home it may ensure that his wife gets her fair share of his immense fortune. Robyn didn’t list a separation date in her divorce papers, but Mel’s response has their date of separation as August 26, 2006, about a month after his infamous DUI. According to TMZ, the separation date is important as it is used in determining which assets to divide. Was Mel catting around on Robyn before their separation? The Gibsons have issued a statement that they will strive for integrity and privacy in their divorce for the sake of their family, but the tabloids are sure to dig up more as this proceeds.