In 2007’s Run, Fatboy, Run, Simon Pegg played a security guard training for a marathon, but even there he never ran the way he runs in Star Trek Into Darkness when his character, Enterprise chief engineer Scotty, sprints down a long corridor at full speed. The afternoon he shot that scene he thought he was going to be filming a lot of dialogue, but director J.J. Abrams had other ideas.

“I ran the length of it three times,” Pegg says on a recent visit to San Francisco. “J.J. said, ‘You have to run from there to there,’ and I did it once and I’ve run as fast as I’ve ever run since I was a kid. The quad bike that was filming couldn’t keep up. I just completely went for it. I felt so free. It was like being a child again.

“I got to the end and all the crew applauded. I felt so good about myself. Then J.J. said. ‘That was great. Can you do it again?’ ‘Yeah, no worries. Give me one minute.’ I did it after that and felt slightly funny after that, like something wasn’t right. And then J.J. said, ‘Just once more,’ and I did it, and I was convinced by the time I slowed down that something was going to happen, so I walked off set very quietly and just waved to everybody. And threw up.”

In a weird way, Pegg’s discomfort is a tribute to the sheer scale of the movie. As Capt. James T. Kirk (Chris Pine) and his crew face a mortal threat in John Harrison (Benedict Cumberbatch) and even greater forces, the story is epic. But so is the filmmaking behind it.

“The set we have now is biggest ever rendering of the Starship Enterprise in the history of the Star Trek story,” says Pegg. “We had a bridge that was connected to a corridor that went through to Med Bay, Engineering and the transporter room. So we could do long talking and walking scenes and have a sense of the ship’s size.”

Other sets were equally massive, including the National Ignition Facility (NIF) at Lawrence Livermore Lab, the massive laser that serves Star Trek Into Darkness as Scotty’s natural habitat, the Enterprise engine room.

“NIF was just extraordinary to be part of,” Pegg says. “ Aesthetically speaking, it formed a brilliant bridge between all the clean lines and that fantastically futuristic bridge to the industrial metal of the engine room, which is what J.J. always wanted it to look like, the guts of the Titanic. But in the middle of this you have the warp core, which kind of looks like a perfect mishmash of the two. You’ve got all this steel and yet it’s all modern looking.”

Adds Pegg’s costar John Cho, Star Trek Into Darkness‘ Sulu, “J.J. Is keen on having as much stuff around you physically as much as is possible and using CG as little as possible. It makes it easier for an actor certainly to look up and see things instead of a green felt cloth.”

The physical space might make it easier for an actor to simply act, but Pegg notes, it could be physically punishing – and not just when called upon to race down a long corridor at full speed for multiple takes. He recalls one scene where Scotty and Pike are running when gravity starts to shift.

“The set was too big to put on a gimbal, which is what you’ve seen in films where – like Inception, say, where there’s a corridor that moves – because the set was too big to move, we are on a wire, running on our sides, which is very hard to do,” Pegg says. “It enabled us to have that sensation, but do it on a much bigger scale. It was hard work.” – Pam Grady