Thirty years after actress Natalie Wood died after going on a boating trip with then-husband Robert Wagner and Christopher Walken, officials have reopened the investigation of her death. For years after Wood’s death — which was ruled an accident — suspicions and theories have been raised about what actually happened on the boat that day. Wood’s death is not the only Hollywood tragedy that has been shrouded in mystery and intrigue. Read the twelve most mysterious deaths in hollywood history:

Bob Crane

The Hogan’s Heroes star was found bludgeoned to death in a Scottsdale, Arizona apartment on June 29, 1978. The murder was examined in director Paul Schrader’s 2002 film Auto Focus and A&E’s Cold Case Files.

Crane’s case was reopened in 1990 and led to John Henry Carpenter, a friend of Crane’s being tried for the crime. Carpenter was acquitted in 1994.

David Carradine

The Kill Bill and Kung Fu star was found dead in a Bangkok hotel room closet with a noose around his neck on June 4, 2009.

A private autopsy funded by his family concluded that the actor died from asphyxiation, and that the way the actor’s body was bound allowed him to rule out suicide. Bangkok police said that Carradine’s body was in a sitting position, with a rope wrapped around his neck and attached to a closet bar when a maid discovered him.

Elizabeth Short

Elizabeth Short was a 22-year-old aspiring actress who was gruesomely murdered in Los Angeles. Short achieved fame post-humously when her story was sensationalized by the media, and she was dubbed the Black Dahlia.The case was never solved. A neo-noir novel, The Black Dahlia by James Ellroy, was published in 1987 and was made into a 2006 movie directed by Brian De Palma.

George Reeves

The Adventures of Superman star was 45 when he was found dead lying naked in his bed with a single gunshot wound to the temple in his Beverly Hills home in 1959. And, though the death (which was the subject of the 2006 movie Hollywoodland) was ruled a suicide at the time, his mother commissioned her own separate investigation. Speculation arose that the actor’s ex-lover, actress Toni Mannix, orchestrated a hit on Reeves.

Jack Nance

A regular in David Lynch projects (Eraserhead, Twin Peaks, Blue Velvet), Nance was found dead on Dec. 30, 1996. The cause of death was subdural hematoma caused by blunt-force trauma.

He is believed to have been punched in the head and knocked to the ground during a fight with two men at his local doughnut shop.

Another theory is that he hurt himself in a drunken stupor, as his blood level was 0.24 percent at the time of his death.

JonBenét Ramsey

JonBenét Ramsey was a beauty pageant child contestant who was murdered in her home in Colorado. A strange and twisted tale unraveled in which Ramsey’s parents said that they had received a ransom note just eight hours before her body was found demanding $118,000 in exchange for their daughter’s return. Suspicion remained on JonBenét’s parents, who insisted they were innocent and published a book in 2000, The Death of Innocence. Ramsey’s mother died just before John Mark Karr admitted that he killed Ramsey. He was later released, however, when DNA tests showed he could not have been at the crime scene. Prosecuters cleared the parents, and claim that DNA points to an “unexplained third party.

Marilyn Monroe

The actress’ sudden death was officially ruled a suicide in 1962 when she slipped into a coma after overdosing on sleeping pills. But, there has always been speculation surrounding the events of her death, which saw many items allegedly being removed from her home. Theories have included murder by the mafia in retaliation to President John F. Kennedy and his brother Robert (both of whom she was reportedly having affairs with, and who have also been discussed as possibly orchestrating the murder), as well as an accidental overdose.

Natalie Wood

Actress Natalie Wood was boating off Santa Catalina Island with her then-husband Robert Wagner and Christopher Walken in 1981.Wagner and Walken got into an argument, and Wood went to bed. When Wagner went to say goodnight, Wood was missing. At the time, her death was ruled an accidental drowning, but there have been many questions raised about what actually happened on the boat in the time since. In a surprising move in November 2011, the Los Angeles County Sheriff’s Department reopened its case in the death of actress almost exactly 30 years after her death.

Nicole Brown Simpson

Nicole Brown Simpson and boyfriend Ron Goldman were stabbed to death outside Simpson’s Brentwood, Calif. condo in 1994. Her ex-husband, O.J. Simpson was put on trial for the murders after blood-stained gloves, fibers from Goldman’s clothing were found in Simpson’s home while hair bearing similar qualities to Simpson’s was found at the crime scene along with bloody footprints matching his show size. However, on Oct. 3, 1995, Simpson was acquitted on both counts of murder. No other suspect has ever been found.

Thomas Ince

Known as “The Father of the Western,” Thomas Ince was a silent film star and filmmaker who was aboard the yacht of William Randolph Hearst in Nov. 1924 when he reportedly fell ill. He was brought ashore, and died 4 days later officially of a heart attack. Rumors began circulating that Ince did not die from health problems but that Hearst accidentally shot Ince in the head. The stories goes that Hearst found his mistress, Marion Davies, in a compromising position with Charlie Chaplin, who was also on the boat. According to this theory, Ince ran down when he heard Davies screaming, and was accidentally shot by Hearst.

Tupac Shakur, Biggie Smalls

The biggest mystery about the murders of rappers Tupac Shakur and Christopher Wallace, a.k.a. Biggie Smalls and the Notorious B.I.G., is how can such high-profile cases remain unresolved?

Shakur was gunned down on Sept. 13, 1996 in a drive-by shooting in Las Vegas. He was 25. Wallace was also 25 when he was shot in drive-by on March 9, 1997 in Los Angeles.

William Desmond Taylor

The actor-turned-director, who abandoned his wife and family in New York in 1908, changing his name from Pete Tanner to William Desmond Taylor when he resurfaced years later in Hollywood. Between 1914 and 1922, he directed over 60 films and shorts and was once president of the Motion Picture Directors Association. But, in 1922, he was found dead in his Hollywood home having been shot in the back. Several witnesses came forward saying they’d seen a young, dark-haired man leaving Taylor’s house, but no one was ever arrested. One theory that was raised involved Taylor reporting actress Mabel Normand’s cocaine dealers to the federal government and his death being a possible drug-overdose.