According to previous reports, Black Widow (Scarlett Johansson) would be the lead in fourth run of "Iron Man." The rumor has it that Natasha Romanoff will make the first female Iron Man. However, it seems unlikely for that to ever happen as the fans do not want to see any other actor by Robert Downey Jr to be the Iron Man. Needless to say, Scarlett Johansson's character will not be enough to replace suave Tony Stark.

"Despite his impressive resume, it's a stretch to imagine that Marvel Studios believes he has the presence and charisma to replace Robert Downey Jr. as Iron Man," as per recent reports. The media publication also insists that "Iron Man" franchise will not be able to succeed without Robert Downey Jr in the lead.

Meanwhile, in a recent interview, Kevin Feige revealed that they are planning to do do a Black Widow solo film. The Marvel Studios are very impressed with Johansson's depiction of a secret spy agent.

"We think she's an amazing character. We think Scarlett Johansson's portrayal of her is amazing," he said. "She's a lead Avenger and has amazing stories in her own right to tell that we think would be fun to turn into a stand-alone franchise," Feige said.

Now that Black Widow may have a film of her own, it is unlikely that she will also take on Downey Jr. character in "Iron Man 4." The rumor has it that the movie is set for 2020 release. However, Marvel is yet to confirm this news. Nevertheless, "Iron Man" fans will be hoping to see the film in stipulated year.