Back in 2016, the franchise’s actor told Variety that he would be retiring the role after reprising it in 2008’s fourth installment (simply titled Rambo). "The heart's willing, but the body says, 'Stay home!,'" Stallone said at the time. "It's like fighters that go back for one last round and get clobbered. Leave it to someone else."
Stallone explained to Variety that he was so happy with the fourth film, he didn’t want to try making another. “As an action film, I was very satisfied that it dealt with the Burmese situation. It had one foot in a current event, the longest civil war in history, 65 years at that time. It was so brutal, which civil war is, I was shocked they even gave me an R-rating,” he said at the time. “I said, 'This is probably going to be the last decent film of this genre that I’m going to do as a solo act.' When that was accomplished, I never felt the same willingness to do it again."
Though the 71-year-old’s role hasn’t officially been confirmed, according to Deadline, Stallone is currently finishing the script and shooting is set to begin in September of this year. In the fifth iteration of the franchise, the daughter of one of Rambo’s friends is kidnapped, propelling the vet into a rescue operation. Rambo, who has been working on a ranch, crosses the U.S.-Mexican border to face off against one of Mexico’s most violent cartels and try and get the girl back.
A fifth Rambo has been in discussion since at least 2011, when it was confirmed that writer Sean Hood submitted a screenplay for the final installment, later titled Rambo: Last Blood. The Rambo series first kicked off in 1982 with the film First Blood. Stallone is also currently working on Creed II, the follow up to 2015’s Creed where he reprised his role of Rocky Balboa.