By Nick Romano
April 18, 2016 at 12:00 PM EDT
Jim Spellman/WireImage

Adam Nimoy, the son of Star Trek icon Leonard Nimoy, decided in November 2014 to start making “just a Spock doc.” As he remarked during a panel at the Tribeca Film Festival on Monday night, “I knew that the 50th anniversary of the original series was coming up, and I wanted to do something with him to celebrate that event.”

About four months later, Leonard died and the entire concept of the film changed.

“I was overwhelmed by the response and emotion from fans all over the world,” Adam said. “It was clear to me at that point that I needed to expand the film to include his life, clearly, and his legacy. And then as I began to delve into that quite a bit, it became increasingly clear that my own perspective on my own story was kind of bound up in that.”

Sitting in front of an audience after premiering For the Love of Spock at the festival, Adam remarked, “It’s my gift to the fans to celebrate and process the loss of my dad and Spock.”

In a way, it’s also a gift made by the fans. The film was partly funded by donations to its Kickstarter campaign, which Adam wrote at the time went mostly to post-production, including the licensing of photographs, archival film clips, and — as he revealed during the panel — David Bowie’s “Starman.” In an emotional moment of serendipity, Adam’s son Jonah recorded a cover of the hit song that plays over the film’s credits.

The director said most of his family was involved “either in spirit or actually wanting to participate” in the film, but they were “blown away” by Jonah’s cover at a Los Angeles concert following the music legend’s passing. “I contacted the publisher and they got what I was trying to do and gave us a license,” Adam said.

His sister, uncle and aunt, and step-brother are some of Adam’s other family members featured in For the Love of Spock, which tells of the cultural icon’s ascension to fame and his tumultuous relationship with Adam. He added, “It’s very difficult to cram a man’s life in an hour and 45.”

Producer David Zappone, Access Hollywood resident Trekker Scott Mantz, and Star Trek Beyond star Zachary Quinto joined Adam on stage during the panel. For most of them, the biggest get from the documentary was Leonard’s approach to Spock. “Leonard played Spock who was a character who was suppressing his emotion, and I never realized this before,” Mantz said of the typically cold and calculating alien.

Quinto, who was also interviewed for the documentary, further explained his discussions with the actor, who shared the screen with the younger star in J.J. Abrams’ Star Trek films. “I think that the humanity in my version of it and the version we created in 2009 with J.J. I think it’s a little more bubbling to the surface.”

Adam noted in For the Love of Spock itself that his role in the rebooted cinematic universe was a “high point” for his father. So much so, in fact, that Leonard ended up injuring himself while filming a scene on set. Abrams, another interviewee of the doc, revealed a never-before-told story of how the actor broke his nose, but Leonard insisted they keep filming. “When you injure Spock, you want to kill yourself,” Abrams said during an interview for the doc.

From an audience member brandishing her Enterprise pin to another thrusting the Vulcan salute at the screen, the theater was full of love for Leonard — but there’s still more to be seen. The film featured interviews with the casts of The Big Bang Theory, Star Trek Beyond, and the original series, among others. But Adam said, “We have about 50 hours of unused footage,” including Leonard’s time on Fringe and more of his poetry.

Jokingly, he added, “For the Love of Spock 2?”