Robert Downey Jr has likened working with his Avengers co-stars to running a relay race.
The actor, who is set to reprise his role as Iron Man/Tony Stark in the superhero film, was reunited with co-stars Chris Hemsworth, Scarlett Johansson and Tom Hiddleston, who all agreed that teaming up for the ensemble comic-book adaptation took away some of the pressure.
"It's like a relay race. I'll come in, all exhausted, Chris is fresh, I'll hand him the baton," Robert revealed at Disney's D23 Expo in Anaheim in California.
"He goes 'Oh my God, am I going to look like that at the end of the day?' and I said 'No, no, you're still in your 20s.'"
Chris added: "You get to share the workload a bit, it's nice to play the character in our own film and have a good grip on things."
But the cast remained tight-lipped about plot spoilers.
"We made it all the way around this press line without getting in trouble with our publicist so far," Robert joked.
"I think the thing is, and I think I speak for all of us - we're pleasantly surprised with the result thus far. This is a pretty ambitious idea. Usually I'm the guy where you can read it in my eyes that I hate my job. So, so far it's going OK."