Robert Downey Jr. Says 'The Best Is Yet To Come' In Avengers 4 Set Pic

Robert Downey Jr. is stoking fans' already high hopes for Avengers 4. The Iron Man actor shared a photo from the film's set on his Instagram early Saturday, showing himself holding up the Avengers logo. What's really grabbed fans' attention, though, is the caption, in which he told fans to "get ready" because "the best is yet to come."

We're still slowly learning which Marvel actors will return for Avengers 4, although we do know that just about everyone under the sun has been confirmed for May's Avengers: Infinity War. That movie has more than two dozen heroes currently confirmed alongside a host of side characters, plus whatever surprises Marvel has up its sleeve.

Infinity War will need all the heroes it can get to fight against Thanos (Josh Brolin) and his villainous lieutenants the Black Order. While we know at least a few superheroes will survive the movie, all signs are pointing to the next pair of Avengers movies being fairly fatal for Marvel's biggest names. (Mark Ruffalo even seemingly confirmed as much in an interview, saying that "everybody dies" at the end of Infinity War.) 

As for Downey's Tony Stark, some fans believe he could be dealing with some health issues in the films, basing their theories off a strategically placed shirt rip shown in one of the actor's previous set photos. If Tony does bite the dust in the film, his story should at least get some closure first, with Gwyneth Paltrow's Pepper Potts and Jon Favreau's Happy Hogan both returning for at least one of the films.

"They're all big," co-director Joe Russo previously said of the two films. "It's important for both movies to be distinctly different. It's important for them to have different tones, and different narratives, and different surprises for the audiences. We've worked hard with [writers Christopher Markus and Stephen McFeeley] at ensuring that the films are tonally different and structurally different."

Very little is known about the fourth film at this point, although Marvel Studios head Kevin Feige says it will remain untitled for quite a while, as the title is a spoiler for Infinity War. Captain America: Civil War's Joe and Anthony Russo take on co-directing duties for both of the next two upcoming Avengers movies. Avengers: Infinity War is set for a May 4, 2018 release, while the untitled fourth Avengers film will follow on May 3, 2019.