Despite the numerous speculations on the status of Robert Downey, Jr. top-billing another solo "Iron Man" movie, there is still no certainty whether the actor is really returning for "Iron Man 4" or not.

There is no denying that "Iron Man 4" is one of the most-anticipated and talked-about yet-to-be-confirmed movies ever. According to the latest in the rumor mill, though, there is no chance for the movie to enter production anytime soon as Downey Jr. will start filming his scenes for another sequel to his movies, "Sherlock Holmes 3."

However, it has been learned that the cameras may not start grinding for "Sherlock Holmes 3" soon as well since the script for the said movie is not even done yet. According to Variety, Warner Bros., Village Roadshow, and Team Downey have just developed a writer's room consisting of a select group of writers to work on the script for the said movie.

It has also been learned that "Sherlock Holmes 3" will not begin filming until Downey Jr. is done filming his scenes for "Avengers: Infinity War," which is said to begin in February next year, and it is very likely for the actor to begin filming for "Sherlock Holmes 3" after he is done shooting for the upcoming "Avengers" movie.

Prior to these developments, there have been numerous speculations claiming that Downey Jr. would no longer return for another solo "Iron Man" movie, as, allegedly, he is already too old for the role. On the other hand, there are also rumors saying that he and Marvel did not see eye-to-eye on his talent fee.

In a recent interview, Marvel's big boss, Kevin Feige, said that because of the longevity of the popularity of "Iron Man" and other superhero characters, it goes without saying that they will be portrayed by different actors eventually. However, according to Feige, it may not happen soon in the case of Marvel, insinuating that there is still a good chance for Downey Jr. to star in another solo "Iron Man" movie.

"These characters have been around for 50-plus years, and have been relatively ageless. Sometimes there are alternate stories where the character is younger than they usually are, or older, but they usually maintain a certain age. I think most of these characters that are iconic, like (James) Bond, like Batman, like Spider-Man, like Iron Man, someday will be portrayed by different actors. The good news right now is I don't have to think about that for a long time," Feige said.

More news and updates on "Iron Man 4" should arrive soon.