Did Charles Manson Have 4 More Victims? 'There's an Answer There Somewhere,' Says LAPD Detective

In the early hours of Aug. 9, 1969, Charles Manson’s cult followers entered the Los Angeles home of film director Roman Polanski and savagely stabbed his pregnant wife, actress Sharon Tate, and shot and stabbed four others.

The slaughter continued the following night when the bodies of grocer Leno LaBianca and his wife Rosemary were discovered inside their home. Both were stabbed multiple times.

Though Manson and his followers were convicted of nine killings, many still wonder: Did the savagery end there?

Questions have persisted for decades about some suspicious area murders and whether their deaths were linked to the notorious clan. These unsolved mysteries persist almost 50 years later and two years after Manson’s death at age 83 and are explored in the latest episode of People Magazine Investigates. Titled “Who Killed Jane Doe #59?,” the episode airs Monday, Feb. 25 at 8 p.m. ET on Investigation Discovery. (An exclusive clip is shown above.)

The mystery behind the murder of 19-year-old Reet Jurvetson began soon after she arrived in L.A. from Toronto in the fall of 1969 to visit a man named John she’d met at a Montreal coffee shop. A few weeks later, her body was found in brush off Mulholland Drive. The vicious knife attack and where her body was dumped — about five miles away from Polanski’s home — fueled speculation that the Manson family was involved.

In Vincent Bugliosi’s 1974 book, Helter Skelter: The True Story of the Manson Murders, the author theorized that Jurvetson — who was known as Jane Doe #59 until she was identified in 2015 — might have been murdered to keep quiet after witnessing the Nov. 5 killing of Manson follower John “Zero” Haught.

Haught, whose death at the time was reportedly declared a suicide, died of a gunshot wound to the head on November 5, 1969 after an alleged game of Russian Roulette. Manson family members were reportedly present when the shooting occurred.

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In 2015, when Jurvetson was finally identified, investigators visited Manson at Corcoran State Prison looking for answers, but the former cult leader denied knowing her. Police also flew to Montreal to interview an artist who met John and Jurvetson at a local café. The artist provided detectives with two sketches, which were later released by police in the hopes of tracking down the two men. But their identities still remain a mystery.

“John is the best lead we have,” LAPD lead investigator Lou Rivera now retired told PEOPLE in an earlier interview.

Eerily, Jurvetson’s body was discovered on the same stretch of road as the remains of 17-year-old college student Marina Habe, another victim of multiple stab wounds. Habe, who was home for the holidays, disappeared from her West Hollywood driveway after a night out with friends on Dec. 30, 1968. Her body was discovered on New Year’s Day.

Back then, police also explored whether Jurvetson’s case was linked to the murder of 19-year-old Doreen Gaul. Gaul had been in L.A. six months when she and her friend James Sharp, 15, were found fatally stabbed in a downtown alley on Nov. 21. 1969.

Police interviewed Manson follower Bruce Davis a few years later in prison after they learned he lived in the same housing complex as Gaul, but he denied knowing the two and it’s unclear if he lived there at the same time as her. Later, another man confessed to the murders, claiming he and a partner killed the teens in a botched robbery, but the two were never charged and have since died. Evidence in the case was destroyed decades ago, leaving Gaul’s case in limbo.

Retired LAPD detective Cliff Shepard hopes that one day there will be firm answers in all four deaths. “It’s just being lucky,” he says. “There’s an answer there somewhere.”

People Magazine Investigates: Who Killed Jane Doe #59? airs Monday, Feb. 25 at 8 p.m. ET on Investigation Discovery.