One of the most enduring things about Star Trek is the bond between James T. Kirk and Spock.
The passionate captain of the USS Enterprise relied on his hyperlogical first officer for frank advice in hairy situations, and together the two saved the crew from certain death countless times.
But that kinship extended far beyond just the characters onscreen.
William Shatner, who played Kirk, and Leonard Nimoy, who played Spock and who died last February, shared a close relationship in real life too.
"He was the brother I never had, as we used to say to each other," Shatner said Saturday, during a question-and-answer session at San Diego Comic-Con. "He was my brother."
Shatner wrote a book on the topic, called "Leonard: My Fifty-Year Friendship with a Remarkable Man." Published earlier this year, it shares stories of the actors' lives on set, as well as personal tales of their family struggles.
On Saturday, Shatner talked about how casts of long-running TV shows -- he used the phrase "families of actors" -- tend to grow apart after a show ends. That's because people get busy.
"You genuinely love that person, but you never see them again," he said. "Because things are in your way -- another show, another thing."
But with Nimoy, it was different, because Star Trek still kept them together. They remained close because they both still did press and promotion for the show.
Star Trek has been one of the biggest draws at this year's convention, as the iconic sci-fi property celebrates its 50th anniversary. Aside from the new film's premiere -- where organizers went all out with a fireworks show and a concert from the San Diego Symphony Orchestra, which played the movie's score -- there have been several panels and exhibits on the show. Those included a panel on the science of Star Trek and an exhibit of artwork commemorating its characters. One brewery even debuted an official Star Trek beer.
The panel with Shatner featured actors from several different incarnations of Star Trek as well, including Brent Spiner, who played Data on "Star Trek: The Next Generation," Scott Bakula (Jonathan Archer on "Star Trek: Enterprise"), Michael Dorn (Worf on "Star Trek: The Next Generation" and "Deep Space Nine") and Jeri Ryan (Seven of Nine on "Star Trek: Voyager").
Executive producers from the new film, "Star Trek: Beyond," which premiered at Comic-Con on Wednesday, were also there. They included Bryan Fuller, Heather Kadin and Rod Roddenberry, son of Star Trek creator Gene Roddenberry. And the name of the upcoming Trek TV series, which is due in 2017 from CBS, was revealed too: "Star Trek: Discovery." The show will feature a new starship, the USS Discovery.
On Saturday, the show's cast and crew talked about how important Star Trek is in today's world.
"The state of our country today terrifies me," said Fuller. "We need something like Star Trek to remind us that collectively as a human race we're going to get our shit together, and we're going to build a better future."
"And we have to start working much harder on that today," he said.
Disclosure: CBS, CNET's parent company, owns the television rights to Star Trek.