STAGE TUBE: CBS's 48 HOURS to Reveal Exclusive Footage on Natalie Wood Death

Related: Previews & Teasers, News, CBS's 48 HOURS

Since 1981, the drowning death of Hollywood star Natalie Wood has been surrounded in mystery. Now, as Los Angeles County Sheriff's Department Homicide detectives continue to investigate her death, 48 HOURS will reveal more evidence that raises additional questions about the official theory of what happened that fateful night.

CBS News 48 HOURS will reveal for the first time that Los Angeles County Sheriff's Department homicide detectives have visited the Splendour, the vessel where Wood was last seen alive, twice – the second time with the yacht's captain, Dennis Davern. 48 HOURS was the only news organization there when detectives combed through the ship – testing the various theories of what happened.

An updated edition of 48 HOURS PRESENTS Vanity Fair: HOLLYWOOD SCANDAL includes the exclusive footage of police, along with Splendour captain Dennis Davern, returning to the boat he hadn't seen in three decades. Also revealed are audiotapes of Wood's sister, Lana, telling Wood biographer Suzanne Finstad what she says Davern told her about the incident in 1992. These tapes have never been heard publicly before.

Wood drowned off the coast of Catalina Island in California in November 1981 after she went missing from the Splendour. Also aboard that night were Davern, her husband, actor Robert Wagner, and her friend and fellow actor, Christopher Walken. Davern has changed the story he initially told investigators. He tells 48 HOURS that Wagner and Wood got in a terrible fight that carried out onto the deck.

In 2001, Finstad taped a conversation with Lana Wood, which she played for 48 HOURS. In the call, Lana Wood describes what she says Davern told her about her sister's last night. Lana Wood told Finstad, "He said that it appeared to him as though RJ shoved her away. She went overboard. Dennis panicked and RJ said, 'Leave her there, teach her a lesson.'" Wood also told Finstad that Davern believed it was an accident: "You know, [Wagner] didn't mean for her to drown. But he didn't run to her aid." Authorities have heard Finstad's tape, but aren't commenting.

Wood was found floating in the water wearing a red down jacket and flannel nightgown. After a two-week investigation the death was ruled an accident. In July 2012, the Los Angeles Coroner's office reclassified her death certificate from an accidental drowning to "drowning and other undetermined factors." The Los Angeles County Sheriff's Department classifies the investigation as "open."

The Natalie Wood investigation is part of a 48 HOURS and Vanity Fair special looking at Hollywood scandals that also features pieces on the 1958 stabbing death of Lana Turner's boyfriend Johnny Stompanato.