No, we're not kidding. Up until now, 'It's Always Sunny in Philadelphia' season 8 has been something of a question mark to us, with the most revealed before the October 11 premiere being that of its inspired anime teaser. Now, the FX series has landed a guest star of A-list proportions, but when will the magnanimous "Diddy" (is that still his name?) appear? And what shocking twist will rock Charlie Kelly's world in the premiere?