In 1992, after NBC's Today program briefly referred via a caption to her alleged connection to the assassination, Irv Kupcinet described the broadcast as "an atrocious outrage" and "calumny".

Kupcinet made her acting debut at age 13 in the Chicago production of Anniversary Waltz and went on to attend Pine Manor College for a semester, eventually studying at the Actors Studio in New York City.

In addition to guest spots, Kupcinet had a regular role in the prime-time series Mrs. G. Goes to College (retitled The Gertrude Berg Show during its short run).

[4] Kupcinet's last onscreen appearance was on Perry Mason in the role of Penny Ames, in an episode entitled "The Case of the Capering Camera".

[8] She made her debut on the public stage at just five and a half months old as a model, her mother arranging for her to appear in baby clothing and accessories advertisements.

In the years that followed Karyn's modelling career continued steadily, she appeared in advertising campaigns in national newspapers, magazines and then TV commercials.

[10] When she left for California at age 20 to try her hand at motion pictures she already had a substantial body of professional acting work under her belt, having appeared in; 'Apollo of Bellac' - 'The Royal Family' with Linda Darnell.

She loved the stage and would prove her mettle starring in a production of 'Father of the Bride', appearing for 15 gruelling weeks in Florida opposite veteran actor Pat O'Brien.

[11] It was reported that she originally appeared on screen as Tammy Windsor and officially as Karyn Kupcinet in the movie 'The Ladies Man' (1961) starring Jerry Lewis.

Before her career was tragically cut short Karyn made a great start, she appeared credited and unaccredited in 31 movies, television shows and TV commercials.

In December 1962 she filmed a guest-star appearance on The Wide Country and had her first meeting with one of the series' stars, Andrew Prine,[13] and began dating him.

[citation needed] The Los Angeles County Sheriff's Department later determined Kupcinet had delivered threatening and profane messages, consisting of words and letters she had cut out of magazines, to Prine and herself.

The pressure to stay thin intensified after Kupcinet arrived in Hollywood, and she soon began abusing diet pills along with other prescription drugs.

[2] A Los Angeles Times interviewer, assigned to help Kupcinet promote The Gertrude Berg Show in March 1962, noted her talking exclusively about food and her weight.

Rubin and Hathaway told detectives the three of them watched television, including The Danny Kaye Show, and drank coffee until Kupcinet fell asleep next to them on the couch.

Mark initially assumed that she had died from a drug overdose; upon searching the apartment, investigators from the Los Angeles County Sheriff's Department found prescriptions for Desoxyn, Miltown, Amvicel, and other medications.

[2][13] They also found a note written by Kupcinet that reflected in some detail her emotions regarding issues in her life and people she admired.

[16] Neither the sheriff's office nor the Los Angeles Police Department had received a report of a baby found abandoned anywhere in Kupcinet's apartment building on the day before or after the murder.

[25] Although public suspicion fell on Andrew Prine there was a more compelling suspect to Karyn's parents, that evidence pointed to another, actor/producer David Lange (1936-2006).

Police suspect the unidentified caller had informed him of Karyn's death, but he chose not to appear on the scene because he already knew what had happened.

Essee and I pressed the sheriff's police to pursue such a revealing statement, but their response was that they had tried with no success because Lange by this time had moved into the house of his sister, Hope, and she had retained attorneys who refused to let him answer any questions...

But no follow-up was done.” [28] Kupcinet's death was first mentioned in connection with the John F. Kennedy assassination in 1967 by researcher Penn Jones Jr. in the self-published book Forgive My Grief II.

[20] Jones speculated Karyn had been murdered by representatives of the Italian-American Mafia as a message to her father to remain silent about why Kennedy and Oswald had been shot.

[20] In 2013, the Ventura County Star commemorated the 50th anniversary of the Kennedy assassination with a long article about the unknown woman who had formed the basis of Penn Jones' conspiracy theory.

Irv Kupcinet had been friends with Sam Giancana, Tony Accardo (1906-1992) and other Mafia dons for decades; as such, it isn't surprising that conspiracy theories surfaced linking the two events.

It didn't help matters that Kupcinet turned up at the Los Angeles County Sheriff's Office with old friend, Mafia lawyer and "fixer" Sidney Korshak (1907-1996) representing him, also handling the release of his daughter's remains for burial.

It undoubtedly raised law enforcement eyebrows as it did conspiracy theorists; Korshak's other clients included Al Capone - Sam Giancana - Moe Dalitz (Los Vegas syndicate head) and Jimmy Hoffa.

It created a frenzy of speculation around Karyn's death and drew them into silly conspiracy theories to kill JFK which Irv Kupcinet hated, not least due to his longstanding friendship with the Kennedy family.

[11][2][33] In the early 1990s, during the production and subsequent release of Oliver Stone's film JFK, Irv Kupcinet attacked the movie and the conspiracy theories surrounding it.

[20] When the film's box-office success led to a wave of media attention about Kennedy conspiracy theories, NBC's Today program broadcast a list of mysterious deaths, including that of Karyn Kupcinet.