Fans of the Marvel Cinematic Universe have already welded together the character of Tony Stark and actor Robert Downey, Jr. and it seems that it will not be easy for many to see another actor putting on the iron suit. But while followers of the franchise are eagerly waiting for a sequel to Iron Man 3, Iron Man 4 plot rumors will just be rumors until Marvel and Disney sign up RDJ.

In an interview with Entertainment Weekly last July, RDJ said, "It's down to Kevin [Feige, the president of Marvel Studios] and Ike [Perlmutter, the CEO of Marvel Entertainment] and Disney to come to us with what the proposal is, and that's on us to agree or disagree. When things are going great, there's a lot of agreement."

RDJ doesn't seem to have qualms playing another Iron Man movie though. As early as last year, he already told Screen Rant, "Iron Man 3 was supposed to answer all the questions for the audience, cure all of my uncomfortable moments in the past with playing this character, and get in every idea that fell by the wayside in the last three movies. And then we shot the movie and I still feel there's a couple other things we've gotta do."

At any rate, Marvel had already announced in July that the Marvel Cinematic Universe will expand until 2019. The company already pegged dates on when they will release upcoming superhero movies, although they're pretty tight-lipped about details.

After the showing of the Guardians of the Galaxy last August 1, the next one will be Avengers: Age of Ultron, which will be shown on May 1, 2015. Two and a half months later, on July 17, 2015, it will be Ant-Man; then Captain America 3 will roll out in theaters on May 6, 2016. Marvel fans will then welcome Doctor Strange on July 8, 2016.

The sequel to Guardians of the Galaxy will be shown on July 28, 2017. Marvel has also marked Nov. 3, 2017; May 4, July 6 and Nov. 2, 2018, and May 3, 2019.

Fans can speculate on which movies would fill out the remaining dates. Variety mentions possibilities, including Avengers 3, Thor 3, and standalone films for Black Widow and Black Panther. Followers can only hope that one of those blank dates is reserved for the fourth installment of the Iron Man franchise.