Joe Russo and Anthony Russo (Captain America: Civil War) are currently filming Avengers 4 in Atlanta, Georgia, which is set to close out Phase 3 of the Marvel Cinematic Universe. With Avengers: Infinity War not coming out until next year, it's raised a lot of questions about the fourth Avengers movie. Like, who will be in it? Odds are, at least one major character is going to meet their demise at the hands of Thanos. But now, thanks to Robert Downey Jr., we know at least four major characters who are going to be back for Avengers 4.

Robert Downey Jr., who only recently confirmed his own involvement in Avengers 4, took to Instagram to share a photo of his fancy new chair that he'll be using on set. It just so happens that there are three other chairs in the background, confirming that Paul Rudd will return as Scott Lang/Ant-Man, Scarlett Johansson will return as Natasha Romanoff/Black Widow and, last but certainly not least, Chris Evans will be back as Steve Rogers/Captain America. Or Nomad. That's a bit unclear right now with Evans specifically, but either way, he'll be back. Here's what Downey had to say about the picture.

"New flick, new short chair. #lumbarsupport #marvel #bts"

While fans are probably happy to know Iron Man is getting the lumbar support he needs, they're surely much more interested to know that three of the core heroes from the MCU are going to survive Avengers: Infinity War alongside Tony Stark. Paul Rudd was recently featured in a set photo, so his inclusion was all but guaranteed. And, for that matter, it was pretty much assumed that Black Widow and Steve Rogers would be back as well, but nothing is certain at this point.

Avengers: Infinity War is going to feature Steve Rogers as we've never seen him before. We know he dropped the mantle of Captain America at the end of Civil War. Thanks to the poster, and the description of the San Diego Comic-Con/D23 footage, we know he's rocking a beard and in full-on Nomad mode. We also know that Black Widow is blonde. How those things play out in Infinity War will no doubt affect how they're portrayed in Avengers 4. As for Scott Lang? At this point, it pretty much seems like he's just Scott Lang, except he now has to help fight Thanos.

Related: Tony Stark's Final Snap Revisited in New Avengers: Endgame BTS Video

Avengers: Infinity War arrives in theaters on May 4, 2018, with Avengers 4 set to follow a year later on May 3, 2019. There's still a great deal of uncertainty surrounding both movies, but at least we know that Iron Man, Black Widow, Steve Rogers and Ant-Man will be around for the majority of it. You can check out the Avengers 4 set photo, courtesy of Robert Downey Jr.'s Instagram, for yourself below.

Ryan Scott