After Iron Man Three we thought the solo series of the Armored Avenger was all over. After all, there's no Iron Man film in Phase Three. Oh, and also Robert Downey Jr said they were done. And looking at the expanding Marvel Cinematic Universe that makes sense - the studio wants to introduce a whole lot of franchises starring people who don't get mega massive cuts of the back end (Downey makes so much money on each of these movies it's kinda obscene). But now Downey has changed his tune.
"I feel like I could do one more," Downey told Nightline, when asked about the future of Iron Man solo movies.
If he were to do one more - and that's a big if - it would have to be in Phase Four, some time around 2020. BTW, there's a guy called Arno Stark, aka Iron Man 2020, so that would be a cool year to have an Iron Man movie come out (he was introduced in the 80s, when 2020 was a fucking enormous distance in the future). Anyway, by that point a new Iron Man film would probably feel like an event and a half, even though Tony keeps showing up in Marvel movies left and right - he's gonna be in Spider-Man: Homecoming next.
It's a smart move for Downey. He has all the money in the world, sure, but he hasn't found another franchise that allows him this sort of public exposure. The kid from Less then Zero is going to end up eulogized as Iron Man when he finally goes - this has become the career-defining role for him. And he's having fun doing it (and he has to do almost no physical work - they paint the whole suit on him via CG and most of his Iron Man work is done with his face right in the camera). so why let that train roll to a stop?