Last Updated 6:27 p.m. ET
Robert Wagner is not considered a suspect in the death of his wife, actress Natalie Wood, the Los Angeles County Sheriff's Department said Friday.
Lt. John Corina said new information deemed "substantial" has prompted homicide detectives to re-open the case, but that Wood's Nov. 29, 1981 death is still considered an accidental drowning.
A yacht captain has come forward to say that he lied to investigators about the mysterious case.
Wood, a three-time Oscar nominee famous for roles in "West Side Story," "Rebel Without a Cause" and other Hollywood hits, was 43 when she died. She and Wagner, star of the TV series "Hart to Hart," were twice married, first in 1957 before divorcing six years later. They remarried in 1972.
In a special to air Saturday on CBS at 10 p.m. ET/PT,Dennis Davern, the captain of the Wagners' boat, said, "I believe that Robert Wagner was with her up until the moment she went into the water."
Wood drowned after spending several hours drinking on Catalina Island and aboard the Splendour with Wagner, fellow actor Christopher Walken and Davern.
For 30 years the story had been that Wood fell overboard -- and no one knew how or when. But Davern tells "48 Hours" he believes Wagner did know, and did little to help.
Daven tells "48 Hours," "I said to Robert Wagner, 'Maybe I should turn on the search light.' He said, 'Don't do that.'"
Wagner and the captain both told investigators the last time they saw Wood she was in her stateroom getting ready for bed. But what's different about the captain's story now is he says Wagner and Wood had been arguing, and that, "the fighting went back to the back of the boat and they just carried on and carried on. And then it was quiet."
The fourth person on the boat that night, Walken, had met Wood on the set of the film "Brainstorm." In a 2009 autobiography, Wagner admitted he'd had an argument with Walken on deck. He was so mad, he wrote, that he smashed a wine bottle. But Wagner told CBS "Sunday Morning" rumors about how Natalie Wood ended up overboard are conjecture.
"If I had heard anything or known anything," he said, "we would have done anything if we'd heard anything. Nobody knew what happened."
According to The Hollywood Reporter, Walken has hired Mathew Rosengart, a former federal prosecutor, to advise him in the inquiry, and the actor is expected to cooperate fully. Sources told THR that investigators do not consider Walken to be a suspect.
The coroner's autopsy indicated Wood had died by accident, attempting to board a rubber dingy off the Splendor, when she fell and drowned.
"That story is 100 percent false," Davern said in a preview of the "48 Hours" special. "Natalie would never, in a million years, take that dingy out by herself. She would have gotten me."
It is not the first time Davern has contradicted statements he and others made to investigators after Woods' death. The magazine notes that he has told his story through tabloids, and has been shopping for a book deal for years.
Corina said today the Sheriff's Dept. had "sources with additional information" that were found credible enough to take another look at the case.
"Her death was ruled an accident, an accidental drowning. That's what it is," said Corina. "If our investigation at the end of it points to something else, then we will address that."
Corina said Wagner has not been contacted, and would not comment on possible conversations.
He said he was not concerned with the fact that Davern is reportedly trying to sell a book. "That seems inconsequential to us," he said, but added, "Having already just the media attention we received already on this that we generated calls and people who have remembered things from back then or didn't talk to the police and now want to tell their story, already people are coming forward and want to talk to us."
He surmised that the 30-year anniversary of Wood's death may have jogged some memories.
Corina did did not know if Wood's body will be exhumed.
He also would not comment on whether the information received recently conflicted with information investigators had when the ruling on Wood's death was made. Corina said that if someone lied and inhibited the investigation 30 years ago, they might face charges.
Appearing on the Vanity Fair special, L.A. Country Sheriff's Detective Duane Rasure - who was the original investigator on the case - questioned Davern's comments about Wagner: "That's like saying Robert Wagner pushed her overboard. That's a murder investigation. But I don't believe him."
Also interviewed on the Vanity Fair special are Marti Rulli, a longtime friend of Davern's who has spent 30 years investigating Wood's death; Roger Smith, the paramedic who took Wood's body to shore; Marilyn Wayne, who was on a nearby boat that night; and Mart Crowley, a close personal friend of Wood and Wagner, who also questions Davern's assertion. "To infer that he stood by ... and didn't dive in to save her is just absurd ... to anyone that knows anything about their relationship."
In the magazine, Davern is quoted as saying that Wood and Wagner fought in their cabin before the actress disappeared. Coroner's officials ruled her death an accidental drowning, perhaps caused by her slipping off the boat while trying to tie down a dinghy.
Wood's death sparked tabloid speculation that foul play was involved, but Wagner and Wood's sister have dismissed any suggestion the actress' death was anything more than an accident. Coroner's officials at the time agreed, writing that Wood was "possibly attempting to board the dinghy and had fallen into the water, striking her face."
Sheriff's officials are hoping for tips from the public may shed new light on how Wood - who was afraid of being in the water - ended up drowning.
"Although no one in the Wagner family has heard from the LA County Sheriff's department about this matter, they fully support the efforts of the LA County Sheriff's Dept. and trust they will evaluate whether any new information relating to the death of Natalie Wood Wagner is valid, and that it comes from a credible source or sources other than those simply trying to profit from the 30 year anniversary of her tragic death," Wagner spokesman Alan Nierob wrote in a statement.
Lana Wood wrote in a biography on her sister, "What happened is that Natalie drank too much that night."
Wagner wrote in a 2008 autobiography that he blamed himself for his wife's death.
"Nobody knows," he wrote. "There are only two possibilities; either she was trying to get away from the argument, or she was trying to tie the dinghy. But the bottom line is that nobody knows exactly what happened."
Later in the book, Wagner wrote, "Did I blame myself? If I had been there, I could have done something. But I wasn't there. I didn't see her."
He wrote that he has never returned to Catalina Island.