Robert Downey Jr. gives emotional speech at Avengers: Infinity War premiere

Ten years of the Marvel Cinematic Universe has been an emotional rollercoaster - not only for fans, but for its cast and crew.

At the centre of it all, in a symbolic way, stands Robert Downey Jr., whose Iron Man initially launched the film franchise and still encompasses much of its heart and leadership.

The actor took to the stage for Avengers: Infinity War's LA premiere to pay tribute to his co-stars and directors, while touching upon what exactly these heroes mean to the world.

“I want to talk about the past, present, and future,” Downey Jr. told the crowd (via Entertainment Weekly), before referencing his past struggles with addiction. “The past for me was 30 years of dependency, depravity, and despair... otherwise known as ‘An Actor Prepares!’"

"The present is this moment of glory for all of us. And the future…? That is always uncertain. But looking at these friends behind me,” he added, turning back to his co-stars, “it seems like things might brighten up after all."

“If you play a superhero in one of these movies, and it works, you become a big star!” Downey Jr. said. “And it... is... meaningless. Unless you use that to achieve something higher. You have to take direction from peers, and your family, and occasionally even an actual director.” He added that directing a Marvel film is "extremely dangerous" and that "it's like a crucible. You either come out steel or dust."

He followed his comments with a jab at the MCU's lack of diversity behind the camera, while praising recent efforts to change this, singling out Captain Marvel's directing duo Anna Bowden and Ryan Fleck. "Now at least half a directing team is female," he said, before calling for more women behind the camera. “Making these movies is so taxing that it is clearly a woman’s job. It’s essentially gestation. But we don’t know how to do that," he said.

He then praised Black Panther's incredible box office success, earning $1.3 billion worldwide so far. "Wakanda rules the day and rightfully so," he said, before turning to star Chadwick Boseman to give him the crossed-arm salute. "By the way, Wakanda forever! I can do that as an honorary black man: Tropic Thunder, 2008."

Downey Jr.'s joke referenced his role in the satirical comedy film, which saw him play a misguided white actor who attempts to play an African-American soldier in a war epic.

“This is the MCU, right in front of you,” he then proclaimed, gesturing to those gathered onstage. “It’s all about fighting for equality. The whole idea is to make space for others to succeed, and exceed our expectations. [The movies] are inviting us to surrender and love and be of service. They are metaphors for how our world should be — or could be one day, if we fight for it."

He then praised his Iron Man co-star Gwyneth Paltrow and the film's director Jon Favreau, before realising it was time to wrap up. "I think this might be the greatest speech ever written!" he joked. "Or maybe I'm just emo and exhausted."

Avengers: Infinity War hits UK cinemas 26 April.

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