Hollywood actor Robert Downey Jr. shares that the "The Avengers" movie is the one instance in his life when everything has gone well.

The actor reprises his role as Tony Stark or "Iron Man" for the new film which boasts an all-star cast including Scarlett Johansson, Samuel L. Jackson, Chris Hemsworth, Tom Hiddleston and Chris Evans.

Characters such as Captain America, Thor, Black Widow and The Hulk will all appear in the movie and Robert Downey Jr. knows that some fans were concerned about how so many big characters could work together. However, he insists that there is no need for skepticism.

"You know, I'm not one of those people who want to be 'I just don't understand why everything's gone this well!' But that, in this one instance in my life seems to be the situation," the actor told Cover Media.

Robert Downey Jr. first played the character for 2008's "Iron Man" and has not looked back since. He knew there was a lot on the line with "The Avengers" due to the star-studded cast and admits to being fearful of the effect it could have on some of his fellow actors.

"From five years ago, when we did the first Iron Man, to today with all these folks you see up here it honestly couldn't have gone any better," Downey said.

"All three franchises that we've launched so far had to work. If this didn't work than it affected all of the previous franchises extremely adversely and there's also the potential for additional franchises based on how strongly people are reacting to Jeremy as Hawkeye, Scarlett as Black Widow and Mark as The Hulk," he further shared.

"The Avengers" is the group of superheroes that joined forces to protect the earth. The film will hit cinemas in Australia on April 25.