23-Year-Old Rising Star Was Found Strangled in Her Apartment. More Than 60 Years Later, the Case Remains Unsolved

Karyn Kupcinet was just 23 years old when she began making a name for herself in the world of film and television.

The daughter of Chicago newspaper columnist and television personality Irv Kupcinet and the sister of television director and producer Jerry Kupcinet, Karyn seemed destined for the spotlight — until her dream was cut short when the ingenue was found dead in her West Hollywood, Calif., home.

It was 1963 when Karyn’s death was ruled an unresolved homicide; 63 years later, the mystery remains.

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The police investigation was hampered by the fact that Karyn’s nude body lay in her apartment three days before she was discovered. And while police said they believed that Karyn likely knew her murderer, they never established a motive.

Karyn had been bright and well-liked, pursuing her dream of dropping out of junior college and moving to Los Angeles after a family friend — comedian

She would go on to land bit parts in films like Surfside 6, Hawaiian Eye and Perry Mason, but her career slowed.

Per PEOPLE’s early reporting, Karyn faced issues in her personal life and was convicted of shoplifting in 1962 for taking two books, a sweater and a pair of slacks. Months later, she broke into the home of her ex-boyfriend, actor Andrew Prine, and hid in his attic when he arrived home with a date.

The night she was killed, PEOPLE noted, Karyn had been dining out with actor Mark Goddard and his wife before returning to her apartment with friends.

Following the discovery of her body, police gave lie detector tests to Karyn’s ex, Prine, and three other friends, but “the results for all four were inconclusive,” PEOPLE reported.

From PEOPLE in 1976: “The most promising lead fizzled when police examined a packet of threatening letters that Karyn and Prine had received. The threats were spelled out in words clipped from magazines and pasted on sheets of paper. Removing the words, a detective found Karyn’s fingerprints underneath, indicating that she had sent the letters herself.”

As PEOPLE reported in a 1976 retrospective of the case, Karyn’s father still kept a leather-bound album inscribed simply “Karyn” in the living room of his Chicago lakefront apartment, some 13 years later.

“We have a good idea who did it,” Irv told PEOPLE at the time, “but nothing we could ever prove. We still hope the Los Angeles sheriff’s police won’t give up on the case, but the longer it goes on with no real answers, the harder it is to have any hope.”

At the time, Irv said he had not heard from police in more than three years, admitting that the family had offered to hire a private detective and had taken other measures in an attempt to find out what happened to Karyn.