Downey Junior's 'mothering' role
It's hard to imagine Robert Downey Jnr as the authoritarian type, but the actor says he played a stabilising force amid the ever-growing cast of superheroes during the filming of Avengers: Age of Ultron.
"I am an assistant den mother for him (director Joss Whedon) - we're more contemporaries," Downey said at the film's London premiere.
"With some younger talent, they're very exuberant. I remember when I was that way. I kind of feel like I'm the assistant principal."
The 50-year-old plays Iron Man in the film, the sequel to the 2012 blockbuster.