All five captains from the sci-fi franchise's TV shows were in attendance at the 'Destination Star Trek' event at London's ExCel centre this weekend.
The convention broke the Guinness World Record for the largest gathering of fans dressed as Star Trek characters, as well as hosting the UK's first Klingon wedding.
Scott Bakula, Avery Brooks and Kate Mulgrew appeared for a Q&A session with fans on stage with Shatner and Stewart, marking only the second time they have all appeared together.
"I did a documentary called The Captains and I learnt to love every one of them," Shatner told BBC News.
"I would presume getting together is a problem because we live in divergent areas of the world."
Patrick Stewart had earlier missed out on the group's official press photoshoot, but later appeared on stage in front of fans who had paid £95 ($152) each to be there. VIP tickets for the event sold for £3,000 ($4,800) each.
Torchwood star John Barrowman hosted the convention, with fans getting the chance to pose their own questions to the actors.
Each captain revealed that they believed in alien life, while Stewart joked that he would add a Twitter account to the captain's chair.