While fans are still clamoring for the franchise to continue, the next "Iron Man" movie may well star Robert Downey Jr., although only as Tony Stark, while a protégé will be taking on the metal suit.

Speculations suggest that while Downey has already said that he may still reprise his role as the eccentric genius, billionaire, playboy, philanthropist Tony Stark, saying, "I don't know how long I'll do it for... I'll keep playing Iron Man for a couple more years, I guess," the next "Iron Man" film may well star a protégé in the title lead relegating Tony Stark into a mentor role. While this remains unconfirmed, ongoing events in the Marvel comics world may make their way into the Marvel Cinematic Universe.

In the comic books, Stark has given access to his Iron Man suit to Natasha Romanoff a.k.a the Black Widow. She has donned the suit on multiple occasions, but she and Stark had a falling-out following accusations of Romanoff killing Jarvis. This is where it may get complicated since events have deviated in the movie version. In MCU, Jarvis was supposedly killed by Ultron in "The Avengers: Age of Ultron," though his consciousness has been transferred to Vision, with Friday taking over the responsibilities for the Iron suit.

In addition, there are speculations that the MCU Phase 4 will have Scarlett Johansson star in her own "Black Widow" movie. Since "Iron Man 4" will definitely be beyond 2020, it will also belong to the fourth phase of MCU movies.

There are also rumors that if the next "Iron Man" movie will be based on current comics storylines, Tony Stark will more likely pass the baton to a 15-year old young girl named Riri Williams. In the comics, Williams has gotten the interest of Stark after the former reverse-engineered one of Stark's old suits and donned a self-made Iron Man costume.