The Office aired its series finale in 2013, but the beloved comedy is still as popular as ever—with Rainn Wilson's character, Dwight Schrute, always being a fan favorite. Wilson recently spent some time reminiscing about the show on Hey There, Human, his Instagram Live series, where he reconnected with former co-star Craig Robinson. In the midst of their virtual reunion, Wilson came clean about how he still feels bad for the "horrible thing" he did to Robinson when an innocent joke went wrong while filming a scene for the season 8 episode "Mrs. California."

As reported by CinemaBlend, Wilson apologized for an incident on set where he accidentally threw a barbell weight at Robinson's head.

"When I see you immediately I feel terrible, because I did a horrible thing to you once on the set of The Office and it was one of the stupidest things I’ve ever done in my entire life," Wilson said. "For the rest of my life I'll apologize to you ... I had some little scene where I had to run into him and be like, ‘Darryl, we gotta have a meeting. Let’s go down to the warehouse. Come on, let’s go,’ or something like that … And you had on your desk a little desk weight, a miniature barbell … I was like, this’ll be nice. I’ll just pick up this prop and I flipped it in the air and it went bonk! Right in [Craig’s] forehead. He was shocked, and angry, and hurt and an egg swelled up on your forehead."

You can watch the full conversation below:

[h/t CinemaBlend]