The "Iron Man 4" rumors continue to heat up after reports came out that the writer of the third installment was removed from the "Mission: Impossible 5" project. According to Enstarz, Drew Pearce, who wrote "Iron Man 3" was replaced by Will Staples for the next MI series. So this means that the writer will have more time to focus on the fourth installment of "Iron Man".

In a separate report made by Hollywood Reporter, they confirmed the news that Pearce was replaced by Staples. The celebrity website said, "Paramount, Skydance and Tom Cruise have roped in Will Staples to work on the script for the fifth Mission Impossible"

The director of the upcoming MI sequel is Christopher McQuarrie, who has worked with the lead actor before in "Jack Reacher". Will Staples, on the other hand, is known for writing scripts for video games such as "Call of Duty: Modern Warfare 3" and "Need for Speed: Rivals".

The "Mission: Impossible 5" will hit the theaters on Dec. 25 and stars Tom Cruise, Jeremy Renner, Paula Patton, Simon Pegg, and Ving Rhames to name a few.

Since Drew Pearce is finally free, new "Iron Man 4" rumors emerged that Robert Downey Jr. may not return in the new sequel. During an interview with The Edge, the 49-year old actor talked about the possibility of a new Tony Stark.

Robert said, "The smart money is you have to look at everybody's age." He further explained, "I'll put myself at the top of the list. Sooner or later, they've got to start over and get somebody young. I'm not there with them yet."

The New York-born actor also said, "It really is the closest thing to being a beloved contract player with a big old-timey studio that there is right now." Robert added, "When you really think about it at the end of the day, these films are entertainment largely driven by young folks. There is something very honorable about that."

So the "Iron Man 4" rumors may be true because Robert has been giving out hints that he may be replaced by a younger actor. Who do you think would best suit the role of Tony Stark?