John F. Kennedy Jr. 'Was the Last Prince' — See the Trailer for ABC's The Last Days of JFK Jr.

John F. Kennedy Jr. 'Was the Last Prince' — See the Trailer for ABC's The Last Days of JFK Jr.

A new documentary about John F. Kennedy Jr. is digging into the life of late first son — and exploring his family’s ongoing legacy.

“He was the last glimmer of the fantasy,” says writer Michael Gross of John in the PEOPLE exclusive trailer for ABC’s upcoming documentary, The Last Days of JFK Jr. “He was the last prince.”

The documentary features interviews with several close friends of John and his wife Carolyn Bessette-Kennedy, who both died in a plane crash on July 16, 1999.

“I think John F Kennedy Jr. summed up the fascination and attachment many have with him when he spoke to ABC News in 1992. When asked about his father, he said, ‘One of the reasons why he remains a figure that captures our imagination is that his life was uncompleted and his work was uncompleted and there was that sense of promises that were left by circumstances undone,’ ” says executive producer Terri Lichstein.

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“Our documentary is an intimate and personal look at the life of JFK Jr. through new interviews with close friends, and extremely rare footage of his life, and life with Carolyn in those final years and days,” says Lichstein. “I believe it will be a lasting emotional and unforgettable journey for the viewer.”

The Kennedys
The Kennedys

The film tracks Kennedy’s life, from the deaths of his father and his uncle, Senator Robert F. Kennedy, to the struggles he faced growing up as the face of a political dynasty.

The documentary includes interviews from longtime friends, such as Sasha Chermayeff, and two of his ex-girlfriends Christina Haag and Julie Baker.

The interviews paint an intimate portrait of the man and his marriage to Carolyn.

“That was definitely a deep love affair,” Chermayeff tells ABC.

Yet, also one plagued by stressful circumstances.

In the last few weeks of their lives, both Carolyn, 33, and John, 38, were under intense pressure. John’s political magazine, George, was under financial strain and John was looking for a buyer. On top of that, the relentless media attention had added stress to their marriage.

“You can’t really imagine what it would do to a young person to have both his father and his uncle murdered in the same way,” says J. Randy Taraborrelli, author of After Camelot in the documentary. “For John, I think that it made him feel that you can’t waste a moment because he didn’t know how long he was going to be here.”

The Last Days of JFK Jr. will air on Thursday, Jan. 3 from 9 to 11 p.m. EST on ABC.