Tag is a movie based on a real-life group of adult friends who get together annually for a month to play the eponymous touching game. Sounds like a great excuse to keep friendships intact, amirite?

But the rough-housing came at a cost when filming took a physical toll on one of its stars. Jeremy Renner fractured not one, but two arms on the third day of shooting, and the actor finally revealed to EW about what the heck happened.

Co-star Jon Hamm confirmed on The Ellen DeGeneres Show that Renner did indeed injure both arms and had to wear casts for the rest of production, but he didn't get into the specifics of the accident since he wasn't on set that day.

Renner told EW the mishap occurred during a scene in which his character evades his pursuers (played by Jon Hamm, Ed Helms, and Hannibal Buress) by climbing up a pile of "20 to 30 chairs stacked about 20 feet high inside of a community hall."

Unfortunately, the haphazard rigging on the chairs failed him and the actor took a tumble.

I broke along with it and fell on the ground and broke my arms.

In a lot of pain, but unaware of his injuries' severity, the dedicated actor repeated the stunt for another take.

Then I realized, I think something's wrong, so I went to the hospital, and they said it was broken, so I got them wrapped up and then I went back to work and did everything I could do to continue on as we did.

An incapacitated Renner filmed the rest of the movie wearing splints and avoided taking pain medication so he would feel when he was pushing himself too hard.

I couldn't rotate my hands but I could move my arms up and down kind of like a robot, but I would do anything that didn't hurt essentially.

The first week was a little rough just because of the swelling, but the swelling went down after the first week. I would take the splints off as often as I could so I didn't stay in this sort of like arm bent position, stiffened, so I was working through therapy and all sorts of stuff throughout the whole picture but I just limited what I could do with my hand.

Contrary to early speculation that most of the movie used CGI for every scene he was in to edit out his green casts, Renner told EW that the only scene requiring digital rendering was that wretched chair stunt responsible for his unfortunate tumble.

I went back to shoot that day, I didn't take anything out of the cast and they had to put like a clean sleeve over my arm, because I didn't want to take it off right after I just broke it, I needed it to set, I wanted the bone to set, so I think they had to CGI my arm or something in just that one scene, but the rest of it, you know, it all went on okay.

Hamm commended his co-star for pushing through, calling him a "trooper." But as the Avengers actor sees it, he had no other option.

What else do you do, you just stop and cry and everyone go home? You know what I mean? I'd be like, 'sorry guys, I'm not going to use a bow and arrow now in Avengers,' it's silly, so I have to kind of push through so that you can perform for everyone.

H/T - YouTube, EW, Twitter, Indiewire