Conflicting versions of what happened on the yacht shared by Wood, her actor-husband Robert Wagner and their friend, actor Christopher Walken, have contributed to the mystery of how the actress died on Thanksgiving weekend in November 1981.

Two sheriff's detectives are now diving into the mysterious events on the yacht Splendour, although whether they reach any different conclusions than their predecessors remains to be seen. They recently received new, seemingly credible information and heard from potential witnesses who weren't included in the original investigation of Wood's death, sheriff's Lt. John Corina said Friday.

But he said nothing has happened to change the official view that Wood's death was originally an accidental drowning. Wagner, the former star of ``Hart to Hart,'' is not considered a suspect, he added.

Corina released few details about who investigators have contacted or plan to re-interview, but the inquiry will certainly lead them to speak with the three survivors of the trip _ Wagner, Walken and skipper Dennis Davern.

Wood's sister, Lana, was not on the boat, but told CNN's Piers Morgan on Friday that she has spoken with Davern many times and believes her sister did not fall off the boat.

``I don't think she fell, I don't know if she was pushed, I don't know whether there was an altercation and it happened accidentally but she shouldn't have died and that does stay with me and hurt,'' Lana Wood said.

``I would prefer to always believe that RJ (Wagner) would never do anything to hurt Natalie and that he loved her dearly, which he did, and I don't believe that whatever went on was deliberate. I've always cared about him. I always will care about him,'' she said.

Davern said on NBC television's ``Today'' on Friday that Wagner is to blame for the Oscar-nominated actress' death in the chilly waters off Southern California in November 1981, but didn't offer many specifics. For years he has maintained that he heard the famous couple arguing on the boat before Wood went missing and Wagner refusing to immediately search the waters nearby for his wife.

Davern's account is dramatically different from what he told investigators after Wood's body was found in 1981, when no mention of an argument between the couple was made. Wood was wearing a nightgown, wool socks and red down coat when she was found floating off Santa Catalina Island.

The renewed investigation comes at a time when plenty of attention was sure to be focused on Wood, whose beauty and acting in films such as ``West Side Story'' and ``Rebel Without a Cause'' made her Hollywood royalty. Her death stunned the world and CBS' ``48 Hours Mystery'' has been looking into the case for a special airing on Saturday.

Sheriff's officials denied the renewed attention prompted their review, which could take months.

``We're not concerned with the anniversary date,'' Corina said. ``It may have jarred some other people's memories.''

The Splendour is currently docked in Hawaii, where it's used for charter cruises. The current owner said Friday that he was contacted by Los Angeles authorities several weeks ago. He did not reveal details of the conversation.

``I have known for a few weeks that there was going to be a police investigation,'' Ron Nelson, who purchased the boat in 1986, said in an interview with KHON-TV in Honolulu. ``But I didn't know it was going to explode like it did overnight.''

Los Angeles Sheriff's Department officials said they will travel to Hawaii to look at the boat as part of their investigation.

Davern and Wagner agree on one point about the fateful night _ there was a heated argument on the yacht after the group returned from dinner on Catalina. All had been drinking, and here is where the three men's accounts begin to differ.

Davern said he heard Wagner and Wood arguing and its outcome had horrific consequences.

Was that fight ``what ultimately led to her death?'' Davern was asked by ``Today'' show host David Gregory.

``Yes,'' Davern replied.

``How so?''

``Like I said, that's going to be up to the investigators to decide,'' Davern responded after a long pause.

Wagner acknowledges a fight took place on the Splendour, but in his best-selling 2008 memoir ``Pieces of My Heart,'' he wrote that the fighting was between him and Walken. The disagreement began over the acting profession and led to Wood retreating to her cabin, while the dispute raged on between Wagner and Walken. Later Walken went to bed, according to Wagner, who, after staying up with Davern for a while, went looking for his wife and couldn't find her on board. He then noticed that a dinghy attached to the boat _and his wife _ was gone.

Walken, who has rarely spoken about the events that led to Wood's death, denied in a 1982 interview on ``Good Morning America'' that he and Wagner quarreled.

``No, that's not true,'' Walken said when asked if a fight was the reason Wood left the yacht. ``They were very good to me, that family, and that's not true.

``We were having a Thanksgiving weekend, a good time,'' he said.

But Walken told sheriff's detectives that there was an argument, according to a 2000 Vanity Fair piece that included statements from a report by the investigating detective. It also included comments from Davern, who told the magazine that he heard Wagner and Wood fighting before she went missing.

The detective, Wagner and Walken and coroner's officials all have maintained that Wood's death was an accident, possibly caused by her trying to secure the dinghy to the side of the yacht.

``The people who are convinced that there was something more to it than what came out in the investigation will never be satisfied with the truth,'' Walken was quoted in the Vanity Fair piece as saying during an interview in the 1980s. ``Because the truth is, there is nothing more to it. It was an accident.''

Wagner too addressed the uncertainty about what happened in his book.

``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.''

Wagner said through a spokesman that his family trusts the sheriff's department to conduct a fair investigation into Wood's death.

The couple was married twice, first in 1957 before divorcing six years later. They remarried in 1972.