Olivier Martinez Files for Divorce Against Halle ... The Plot Thickens

Olivier Martinez has just filed for divorce against Halle Berry, TMZ has learned ... and the plot is thickening.

TMZ broke the story Halle filed for divorce Tuesday morning, but the divorce petition is nowhere to be found in the system. A source connected to Halle tells us it was filed under pseudonyms.

Apparently Olivier doesn't think fake names are kosher, so his lawyer, disso queen Laura Wasser, has just filed for divorce listing Olivier as the petitioner.

As for why being the petitioner is important, in Hollywood it matters who left who.

Olivier's asking for joint custody of the couple's 2-year-old son, Maceo. As we reported, they have a prenup so money will not be an issue.

We're told Olivier and Halle have not been getting along and last week was a breaking point, after an LAX employee sued Olivier for pushing a car seat into his chest. He also named Halle and we're told she went nuclear on Olivier saying he's responsible for her bad publicity.

We're told Halle and Olivier had a fundamental personality clash. She is "very difficult" and "goes nuts when she doesn't get her way," and Olivier has a temper, though not violent toward her. It was a bad combo.