Kelly Clarkson Covers 'It's Your Thing' By The Isley Brothers | Kellyoke
"It's Always Sunny in Philadelphia" is one of the most successful live-action comedy series of all time, but that wasn't the case when it first aired in 2005. Glen Howerton talks about the show's slow build-up in the early seasons, and the episode when he realized they were finally blowing up. Also, Glen talks about transitioning to his new show "A.P. Bio," and how it's been a dream job for him.