Robert Wagner 'Not Cooperating' As Detectives Uncover New Evidence In Natalie Wood Death—14 Bombshell Photos

Forensic detectives probing the mysterious drowning of Natalie Wood secretly flew “Splendour” boat captain Dennis Davern, one of the last men to see the star alive, to Hawaii so he could walk them through her final moments. Click through RadarOnline.com’s gallery to see all the behind-the-scenes photos.

Natalie Wood, 43, disappeared off the boat “Splendour” on Nov. 28, 1981, while she and her husband Robert Wagner and her Brainstorm co-star, actor Christopher Walken, were yachting off the coast of Southern California.

Forensic detectives probing Wood’s mysterious drowning secretly flew “Splendour” boat captain Dennis Davern, who was one of the last men to see the star alive, to Hawaii so he could walk them through her final moments.

The real-life CSI investigation involved three investigators from the Los Angeles County Sheriff’s Department Homicide Bureau, who conducted a series of top-secret tests.

Cops conducted a series of “noise tests” over four days in a bid to substantiate Davern’s explosive eyewitness account of what he said really took place on that mysterious night in 1981.

Davern — who passed a polygraph test administered to him by police — specifically has implicated Wagner in Wood’s cold case death, and his information helped authorities reopen their files in 2011.

While Wagner has strongly denied fighting with his wife, Davern has provided explosive testimony that the troubled couple had a vicious argument that he heard and partially saw before Wood disappeared off the boat.

What’s more, the police official said a fourth person on the ill-fated boating trip, Wood’s co-star, Walken, also could have heard the fight. “Davern’s recollection of that night was pretty clear,” Lt. Corina confirmed. “We determined that the loud clamoring could be heard in the other rooms below deck.”

While Wagner, 85, has not been named “a suspect” in Wood’s death, the top cop told The National ENQUIRER that he — along with Davern and Walken — is now classified as “a person of interest” in the investigation. He said that determination was made after the L.A. Coroner’s Office changed the cause of Wood’s death from “accidental drowning” to “drowning and other undermined factors.”

Said Lt. Corina: “Of the three, Wagner is the only person who is not cooperating and talking to us. I think it speaks volumes that he won’t speak about his wife’s death … As far as we know, he was the last person to be seen or heard talking to Natalie before she went missing.”

On the night Wood died, Davern has told authorities that Wagner got into a heated argument with Walken. According to Davern, a furious Wagner shouted: “Do you want to f*** my wife?” Wagner then smashed a bottle of wine, and Wood fled the main cabin, seen here during the new investigation.

According to Davern’s recollections, the couple had a brutal fight during which he heard “things objects, possibly people hitting the walls.” At one point, Davern claimed he glanced out of his “pilot house” window and saw the couple on the yacht’s aft deck. He alleged: “They moved their fight outside … You could tell from their animated gestures they were still arguing.” Fifteen minutes later, Davern said Wagner informed him that Wood may have returned to shore aboard the yacht’s small “dinghy,” noting that Wagner appeared “nervous and disheveled.”

Davern said Wagner delayed the search for his wife before the dinghy was found a mile from the yacht – and a mile from where Wood’s body was eventually found. The cops’ new forensic development is considered a significant step in potentially solving the 33-year Hollywood whodunit, according to top Los Angeles private investigator Dan Hanks.

“The police have taken the extraordinary step of recreating what Dennis told them," said Hanks.

Natalie Wood's sister Lana has written an open letter to Robert Wagner urging him to help her get to "the truth" and give her closure over the actress's mysterious death. The letter obtained by the National Enquirer has been penned on the eve of the 33rd anniversary of Natalie's death. Lana appeals to Natalie's husband Wagner to come forward with "any vital information". She writes in part: "I have no animosity towards you and wish you no malice (but) it's been 33 years and I am no closer to the truth about what happened. Never a day goes by that I am not haunted by that dreadful night." She adds: "Speak with and cooperate with the detectives. You can clear your name and conscience and finally afford her friends and family some closure." Natalie was 43 when she died on November 29, 1981. She was sailing off the coast of South Catalina Island with Wagner and actor Christopher Walken when she fell overboard.

Lana Wood has written an open letter to LA District Attorney Jackie Lacey pleading for Robert Wagner to be arrested over the death of her sister Natalie. Lana shared the letter with The National Enquirer as the official investigation into Natalie's mysterious 1981 drowning continues.

Actors Natalie Wood and Robert Wagner outside La Scala restaurant in 1980 in Beverly Hills, California. 

Natalie Wood and Robert Wagner with their children at the Hollywood Christmas Parade on December 19, 1976 in Los Angeles, California.

Robert Wagner Conforts His Daughter Courtney Brooke Wagner At Her Mothers Funeral December 1981. Natalie Wood drowned In A Boating Accident Off South Catalina Isalnd 29th November.