Robert Downey Jr. made an appearance on The Howard Stern Show this week, talking with the SiriusXM host about a variety of topics. They discussed Martin Scorsese's recent comments about the MCU, along with the fact that Downey declined to lobby for a Best Actor Oscar for his performance in Avengers: Endgame. But perhaps the most shocking revelation of the whole interview came right up front, when RDJ admitted to Howard that he came close to a phsyical altercation in the green room moments before he was set to come on air.

So what happened? And who wanted to fight national treasure Robert Downey Jr.? The story is humorous, and shows the restraint Downey has in this later half of his long career. RDJ explained to Howard Stern that he'd experienced a rather awkward encounter in the show's green room with an unnamed Hollywood executive.

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Moments before sitting down for his interview, Downey and his team were watching the show from a set of monitors. The industry executive came into the room, belittling the Oscar nominated actor for standing in front of the Sirius XM monitors. Robert Downey Jr. explains exactly what happened.

"I was just standing out there ... standing in front of the TV screen when this little nebbish bigwig says, 'Out of the way,'."

Robert Downey Jr. went onto explain to this Hollywood executive that he and his small group were just watching the show to get warmed up before having to go on air. The executive wasn't having it though, looking RDJ up and down before asking, "Who the f-k are you?"

Robert Downey Jr. went onto tell Howard Stern that he immediately considered getting physical with the guy, saying he was, "going to have to light this guy up." But cooler heads prevailed, and he decided to just brush off the encounter. He blamed the guy's attitude on his 'bigwig ego'. He went onto say that executives of a 'certain status' in Hollywood "are the master of their environment." He's been in the business long enough to know that these type of guys take issue when they can't control any given situation or the individuals involved within it.

As previously reported, Robert Downey Jr. then went onto talk about his role as Iron Man in the Marvel Cinematic Universe, and even countered some thoughts Martin Scorsese shared rather recently on the state of comic book and superhero movies. The legendary filmmaker doesn't consider them 'cinema'. While Downey welcomes Scorsese's thoughts and ideas on the matter, he doesn't necessarily agree with them. He compared Martin Scorsese's comments to claiming that Howard Stern wasn't 'radio', to nudge at how misinformed Scorsese's controversial statement may actually be.

Robert Downey Jr. took the high road though, glad that Scorsese shared his opinion. 'I appreciate his opinion because I think it's like anything. We need all of the different perspectives so we can come to center and move on." You can watch the video from the Stern show featuring some of RDJ's thoughts on the matter direct from The Howard Stern Show.