Veteran actor CHRISTOPHER WALKEN revealed that a shocking “sex secret” led up to the death of screen legend NATALIE WOOD 30 years ago in the chilly waters off the coast of California, sources tell The ENQUIRER in a blockbuster world exclusive.

Although the tragedy was originally ruled an accidental drowning, the Los Angeles County Sheriff Depart­ment recently announced they were reopening the case based on new evidence from persons including Dennis Davern, the yacht cap­tain on board the Splendour, which carried Natalie, her husband, actor Robert Wag­ner, and Walken the night Natalie died at age 43.

Now the offi­cial probe could explode even more based on the claims that Walken knows of a “sex secret” at the heart of the tragedy.

The information comes from a new witness in the case – 52-year-old interior designer Robin Butillo, who spoke exclusively to The ENQUIRER.

“For 30 years, I’ve never told what I know about Natalie Wood’s death, but I feel it’s time to come forward,” Butillo said.

“This has haunted me for years.”

In 1981, Butillo shared an apart­ment with a close friend of Walken.

She said she and her former room­mate were watching TV together when they saw the reports of Nata­lie’s death.

“We couldn’t believe it – and my friend was deeply concerned about Chris’ welfare,” Butillo said.

“Only hours after her death was confirmed, Chris called…and what he revealed shocked the both of us!

“In the phone call, it was clear that Chris was devastated by the tragedy. He was upset and confessed that a ‘sex secret’ had occurred, leading up to Natalie’s death.”

Butillo added: “While it’s clear Chris had no involvement in Natalie’s actual death, he clearly felt the need to unload his sorrow on his friend.”

The ENQUIRER is withholding the specific details of what Butillo claims Walken al­legedly told her roommate about the “sex secret.” The roommate, now a successful Hollywood business­woman, confirmed she knows Walken.

At the time of the tragedy, The ENQUIRER report­ed that Wagner was “worried and jealous” about a potential relationship between Wood and Walken yet, incredibly, invited Walken to join him and Natalie on their yacht for a Thanksgiv­ing weekend off Catalina Island.

Trouble began almost immediately. At an initial dinner on the island town of Ava­lon, Natalie and Robert got into a boozy argument. Once back on the Splendour, Natalie refused to spend the night sleeping on the yacht and returned to shore in a dinghy with Davern, where the two drank wine in a shared motel room.

In his book, Davern said Natalie admitted to him that Wagner was “out of control” and told him: “I’ll see a lawyer if I have to. Maybe that will send the message loud and clear.”

But The ENQUIRER has learned that Natalie had already made the decision to divorce her husband.

A family insider revealed: “She would have filed for divorce had she returned alive from the ill-fated boating trip. They were having ugly fights for some time. I think she was afraid of him. It was an absolute mistake to have invited Chris on the weekend outing – it made Robert flip out. He couldn’t contain his anger.”

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