School is in session, and this time, A.P. Bio's Glenn Howerton is the student!

The It's Always Sunny in Philadelphia funnyman returns as favorite sarcastic teacher Mr. Griffin

School is in session, and this time, A.P. Bio's Glenn Howerton is the student!

The It's Always Sunny in Philadelphia funnyman returns as favorite sarcastic teacher Mr. Griffin in season four of Peacock's A.P. Bio, back Thursday, Sept. 2.

The beloved ensemble cast also includes Patton Oswalt, Paula Pell, Jean Villepique, Lyric Lewis and Mary Sohn, plus a few surprise celeb cameos. But this season, one fresh face even took Howerton by surprise—especially when he was playing Howerton's onscreen father, "Mr. Mr. Griffin." 

"Bruce Campbell is a childhood hero of mine," Howerton exclusively gushed to E! News on Aug. 27. "I'm not being hyperbolic. Evil Dead 2 changed my point of view, like it made me realize that things were possible. I was like, 'Oh, if you can do that, you can you can do anything, as long as you got the ability to pull it off.' He was just so influential to me as a child. I was honored, and he was great. He was super fun to work with and a sweet guy. It was just a pleasure."