In the bestselling traditions of Seinfeldia and Top of the Rock comes a fascinating and unauthorized deep dive into the longest-running live-action sitcom in television history, from its humble beginnings to its evolution as a critically acclaimed cult classic comedy.

Charlie, Dennis, Mac, Sweet Dee, and Frank are deplorable characters. They will never mature, become more self-aware, or be less self-involved. That’s what the creators of It’s Always Sunny in Philadelphia are committed to—and that’s why the show’s millions of devoted fans have stuck with the cult comedy hit for seventeen seasons and counting.

Back in 2004, frustrated and unemployed actors Rob McElhenney, Glenn Howerton, and Charlie Day drafted a homemade TV pilot. A few months and $200 later (the cost of videotapes, pizza for their friends who volunteered as extras, and a broomstick to tape their boom mic to), It’s Always Sunny in Philadelphia was ready for its network debut. All major parties either passed or wanted creative control. And then came FX, looking to shake up cable TV. Willing to allow McElhenney, Howerton, and Day complete freedom to deconstruct the traditional sitcom, new president John Landgraf agreed to take a chance. No one had any idea how big a success it would be.

With one creative note—the hiring of Danny DeVito—adding the final piece of the puzzle, It’s Always Sunny in Philadelphia has since enjoyed a steady climb to high ratings, critical acclaim, and a place in the cultural zeitgeist. Now, how the show and its creators have accomplished all this is revealed through this in-depth, behind the scenes celebration—as thoughtful, provocative, and engaging as the show itself.