Gene Hackman‘s will has been unveiled — and the two-time Oscar-winner left every penny of his fortune to his wife, Betsy Arakawa — but there’s a big twist.

The Hollywood legend made Betsy his sole beneficiary back in 1995, according to the docs, obtained by TMZ.

What’s interesting is that his three children — son Christopher and two daughters Leslie and Elizabeth — are not named in the will. It was all supposed to go to Betsy … but, the timing of their deaths could change where the money goes.

As we told you … early findings indicate Betsy died from hantavirus, a rare disease that can be fatal … while Gene passed away about a week later due to cardiovascular disease. Officials made it clear Hackman was struggling with Alzheimer’s disease — which would explain why he never called the police about his wife.

Betsy’s will leaves most of her assets to Gene, but there’s a provision which says if they died within 90 days of each other, it would be considered a simultaneous death, and in that case, her will provides all of her assets would go to charity.

New Mexico is a community property state, so assuming there’s no prenup, Betsy’s estate could have a lot of money and her share would go to charity.

As for Gene’s estate … despite the fact he did not include his children in his will, they would presumably get his share since they are the most direct living heirs.

Andrew M. Katzenstein — a prominent California trust and estate attorney — has reportedly been hired by Gene’s son Chris, who’s the oldest sibling … indicating he may challenge the will.

Hackman discussed his difficult relationship with his children over the years … admitting he wasn’t around much during Chris’ formative years. He had gotten closer to his kids in more recent years.

Julia Peters, a representative for the estate of Hackman and Arakawa, has also filed paperwork asking the court to grant a preliminary injunction preventing authorities from releasing any photo or video of evidence of the crime scene — officer body cam footage for example — citing Gene and Betsy’s right to privacy.

As you know … Hackman and Arakawa were found dead in their home last month — and, officials say they believe their bodies had been lying in the house for more than a week.