THOUGH he has travelled to distant galaxies and encountered mysterious civilisations, Captain James T Kirk recalls his encounter with a Glesga taxi driver as a singular experience.

Chris Pine, who returns to the captain's chair in Star Trek Into Darkness this week, arrived in the city to explore Scotland before going on to the University of Leeds. The young Californian settled into the cab and the driver asked if he was enjoying his stay.

"I said 'Well, you know, I just landed and I think England is so beautiful'. The gentleman stopped the cab, turned round to look at me and said, 'You're not in England. You're in Scotland, son.' I loved that, it's one of my favourite stories of the whole trip."

Zachary Quinto, who plays Spock, smiles with the recognition of a fellow traveller. The two have been on the road together a lot lately, publicising the follow-up to director JJ Abrams's £248 million-grossing reboot of the franchise. After Sydney, Moscow, Berlin ("many nightclubs" says Quinto), I catch up with them in London.

Star Trek Into Darkness finds Kirk and the crew of the USS Enterprise a little older but not much wiser about a mysterious new super-villain who has appeared on Earth's radar and is causing mayhem. Made with Abrams's trademark blend of spectacle, strong story, and fully fleshed-out characters, the film gives Pine, Quinto, and the rest – including Simon Pegg as Scotty – the chance to show their acting chops.

The first film, says Pine, was all about establishing who the Star Trek family was. "In this one [JJ] really gets to blow it apart and expand these characters. What was exciting for me is that the brash, self-assured young man of the first film is now becoming a man. In that maturing there's a lot of self-doubt and learning about the importance of humility, all of these great things that are completely in contrast to who we thought Jim Kirk, James Kirk, was at first."

"You can call him Jim," says Quinto.

Quinto admits he wasn't a devotee of the series until he got the job on the 2009 film. When the Heroes star began looking into Star Trek he started to admire the way the series creator, Gene Roddenberry, had broken so many social barriers. Star Trek did indeed boldly go where few series had gone before, particularly with its diverse, international crew (including a Russian officer in the Cold War era), and a landmark multi-racial kiss.

Quinto can be seen as part of that tradition as an out gay man in a blockbuster franchise.

"In the Hollywood studio structure still adjusting to all of the social progress that has been made in the last handful of years, and notoriously exclusive of openly gay actors, I feel really proud that I'm one of the two leads in a multi-hundred million dollar movie," he says.

"I can look at that and say for a kid growing up in this world, it gives them something to look at that I didn't have, and that generations of actors before me weren't allowed to provide. I feel tremendously honoured by that, and I don't take that lightly."

Pine, 32, is from Los Angeles, and Quinto, 35, was born on the other side of the US, in Pittsburgh, Pennsylvania. Both are graduates – Quinto in drama and Pine in English – and their careers suggest Abrams, whose next job is rebooting Star Wars, is not the only one with smarts.

After co-starring with Denzel Washington in Unstoppable, and Reese Witherspoon in This Means War, Pine takes the title role in Kenneth Branagh's spy thriller Jack Ryan, due for release at Christmas. "It's intelligent in the way that Seventies thrillers were, it's like Three Days of the Condor," says Pine.

Quinto starred in the Oscar-nominated Margin Call through his own production company which has the Robert Redford actioner All is Lost premiering at Cannes.

But the question is: does he get to keep the ears? "I might have pilfered a few," he smiles.

Which is highly logical.

Star Trek Into Darkness opens on Thursday.