Robert Downey Jr. will have been playing Tony Stark/Iron Man for ten years, by the time Avengers: Infinity War comes out in 2018. The actor returns as Mr. Stark later this year opposite star Tom Holland in Spider-Man: Homecoming and may yet appear in the currently-untitled fourth Avengers movie, due out in theaters in 2019. As for what comes next for RDJ once he's done playing in the Marvel Cinematic Universe, there are a handful of options.
Although tentative plans for RDJ to reunite with filmmaker Guy Ritchie on a third Sherlock Holmes movie last year ultimately didn't come to fruition, Sherlock Holmes 3 might yet happen at some point, post-Infinity War in 2018 or beyond. Meanwhile, it appears as though the Pinocchio adaptation that RDJ has been loosely attached to star in (as Pinocchio's creator, Geppetto) for years, might be on indefinite hold or dead in the water now. However, in the latest twist, it appears as though RDJ may instead soon be starring in another classic literature adaptation altogether.
Variety is reporting that RDJ has been brought onboard to headline a film adaptation of The Voyages of Doctor Dolittle, based on Hugh Lofting's award-winning 1922 novel of the same name. This version of the story about the famous Victorian-era doctor who can talk to animals is being written and directed by Oscar-winner Stephen Gaghan, coming off his work on last year's Matthew McConaughey-led drama, Gold. Gaghan is also slated to direct the Ubisoft video game film adaptation The Division (also based on a script that he wrote), before he turns his attention to Doctor Dolittle.
Children of the 1990s and 2000s might remember growing up and watching the Eddie Murphy-led Doctor Dolittle movies, which re-envisioned the story of the eponymous doctor as comedies set in the present-day. Rex Harrison starred in a more straightforward (albeit, musical) film version of Lofting's Doctor Dolittle novels in 1967, when he headlined the Oscar-winning Doctor Dolittle. It seems that the RDJ-headlined Doctor Dolittle will be a period-set fairy tale in the vein of the Harrison version rather than the Murphy movies, judging by the track record of the project's producers, Joe Roth and Jeff Kirschenbaum (Alice in Wonderland, Maleficent).
A historical Doctor Dolittle movie adaptation would, among other things, allow RDJ to itch that scratch to make a family-friendly, old-fashioned fairy tale movie that was unable to itch, due to Pinocchio being put on indefinite hold. The actor has yet to fully rule out appearing in an Iron Man 4 at some point within the next few years, even one in which he passes the (figurative) torch to someone else to don the Iron Man armor. Fans of RDJ as an actor in general (read: not just when he's playing Tony Stark) will no doubt be glad to know that he is also planning future non-MCU films to work on, too.