It's Always Sunny in Philadelphia Season 6 Episode 8
The Gang Gets a New Member
The gang opens up a time capsule from ten years ago and discover and find an old picture of them with a lost gang-member, Schmitty (Jason Sudeikis). Dee discovers a check she wrote for her drama teacher for helping her realize her dream. The guys go to bring Schmitty back in, while Dee goes to visit her old teacher.
The boys recall why they originally kicked Schmitty out: Charlie gave them an ultimatum, "him or me." They all start hanging out again and it doesn't take Charlie long to give them the same choice. This time they choose him.
Dee, meanwhile, goes to visit her old teacher that convinces her to give up on her dream, but to teach and inspire others. She gets a job as a substitute teacher, and soon Charlie, out of the gang, comes to visit her at work. He ends up getting a job as a janitor at the school in an attempt to become best friends with Dee. In the end, Charlie's cleaning causes the teacher to get injured.
Back with the guys, they begin the initiation process with Schmitty, but as he mocks their traditions, they get annoyed with him. Once again they kick him out of the gang and go to recruit Charlie back. But it's too late. He's a janitor now.