Nearly four decades after his wife Natalie Wood drowned, investigators are now calling actor Robert Wagner a “person of interest” in her death.

Since 1981, mystery and speculation has swirled around the death of the 43-year-old actress, who had been nominated for three Academy Awards and appeared in the films “West Side Story” and “Rebel Without a Cause”.

She was on a yacht with Wagner, actor Christopher Walken and the boat captain on Thanksgiving weekend of 1981.

After a night of drinking, her body was found floating in the water off California’s Catalina Island.

Investigators initially ruled it an accident, but reopened the case in 2011 to see whether Wagner or anyone else played a role after the boat’s captain said he heard the couple arguing the night of her disappearance.

The coroner’s office amended Wood’s death certificate the next year to include “drowning and other undetermined factors”.

Robert Wagner and Natalie Wood, pictured at the Dorchester Hotel in London in 1972 (AP/Press Association Images)
Robert Wagner and Natalie Wood, pictured at the Dorchester Hotel in London in 1972 (AP/Press Association Images)

Los Angeles County sheriff’s Lt. John Corina told CBS News, in an interview that aired on Thursday, he does not believe the 87-year-old has told the whole story about what happened during the boat trip.

Lt. Corina said: “As we’ve investigated the case over the last six years, I think he’s more of a person of interest now.

“I mean, we know now that he was the last person to be with Natalie before she disappeared.”

Asked whether he believed Wood was murdered, he said: “I think it’s suspicious enough to make us think that something happened.”

After the interview aired, a sheriff’s department spokeswoman, Nicole Nishida, played down the comments, saying there is nothing new with the case.

Investigators have said Wagner has not been interviewed since the probe was reopened.

Police said in 2013 they had tried at least 10 times to interview him but he refused.

Robert Wagner arriving at the premiere of Austin Powers: Goldmember in 2002 (PA Archive/PA Images)
Robert Wagner arriving at the premiere of Austin Powers: Goldmember in 2002 (PA Archive/PA Images)

Wagner has denied any involvement in his wife’s death and no charges have been filed.

His publicist, Alan Nierob, declined to comment.

Conflicting versions of what happened on the yacht have contributed to the mystery of her death.

Wood, Wagner and Walken had all been drinking heavily in the hours before the actress disappeared.

Wagner wrote in a 2008 memoir that he and Walken argued that night.

He wrote that Walken went to bed and he stayed up for a while, but when he went to bed, he noticed his wife and a dinghy that had been attached to the yacht were missing.

AP