Everyone knows who Chris Hemsworth is. Not only does the actor play Thor, but he was just named People’s Sexiest Man Alive. Woody Harrelson, however, didn’t realize that his “Hunger Games” co-star Liam Hemsworth was the “Thor” star’s brother.

In an interview for “The Hunger Games: Catching Fire” from last year that’s been making the rounds again, Harrelson has the major realization that the Hemsworth brothers are related. As Liam is talking to the interviewer, whose first name is also Chris, about his brother’s upcoming film, you can see a look of astonishment cross Harrelson’s face. “Jesus, I never got that he was your brother,” Harrelson says to Hemsworth. “Until just now. I honestly never put that together.”

Harrelson may have helped solved one of TV’s greatest murder mysteries earlier this year in “True Detective,” but when it comes to last names, things go right over his head.

Watch the interview above and fast forward to 3:52 to witness Harrleson’s discovery.

H/T MTV.