Not for the easily offended, It's Always Sunny in Philadelphia is one dark and hilarious sitcom. Still, it garners critical praise and loyal fans with its smart writing. Rob McElhenney, Charlie Day, Glenn Howerton, and Kaitlin Olson star as friends who run Paddy's Irish Pub. Fueled by alcohol, vanity, and selfishness, and joined by Danny DeVito, the foursome has a series of misadventures as high on the laugh scale as they are in their cringe quotient. Though most sitcoms don't joke about crack addiction, abortion, and racism, It's Always Sunny in Philadelphia turns these subjects into comedy goldmines. The Always Sunny book is the perfect opportunity to revisit and expand on inside jokes from the show, and The Gang's best pranks and shenanigans over the years. It also provides an opportunity to extend the show experience through reimagining some favorite plot lines and the further development of backstory. It will be a must have for fans!