In November 1981 film star Natalie Wood, her husband, actor Robert Wagner, and their guest, Natalie’s then co-star, Christopher Walken, were spending Thanksgiving weekend onboard the couple’s 55-foot yacht, “Splendour,” when late one evening the actress disappeared. She was found dead hours later in the waters off Southern California’s Catalina Island.

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Following the initial investigation, Wood’s death was ruled “accidental.” Authorities changed that ruling to “undetermined” more than 30 years later when they renewed the inquiry into Wood’s death amidst new information from the boat’s captain Dennis Davern and two other witnesses. They also named Wagner as “a person of interest.”

Watch: Actress Natalie Wood’s Sister Claims Former Brother-In-Law, Robert Wagner, Has ‘Something To Hide’ In Drowning Investigation

“I can tell you exclusively that they have attempted no less than eight times to speak to Robert Wagner,” claims investigative journalist Dylan Howard in the video above. Howard, who also hosts the podcast Fatal Voyage: The Mysterious Death of Natalie Wood, claims his sources inside the Los Angeles County Sheriff’s Department say Wagner has “refused every overture to speak to police.”

"Someone shouldn't die without knowing what happened to them," says Howard, asserting investigators believe Natalie Wood’s death was the result of foul play. Robert Wagner adamantly denies any involvement with his late wife’s death. He has never been charged in connection with the investigation.

Watch part one of this two-part Dr. Phil Thursday to hear why Howard and Natalie’s sister, Lana Wood, both claim Wagner may have been involved.

Then on Friday’s episode, hear what former “Splendour” captain Dennis Davern claims he witnessed aboard the yacht on the night Natalie Wood died.

Watch: Former Yacht Captain Claims To Recall New Details From The Night Actress Natalie Wood Drowned

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