Exclusive | Danny DeVito nearly died on set of Its Always Sunny in Philadelphia: book

The gang turns twenty.  TV’s most outrageous sitcom “It’s Always Sunny In Philadelphia” is celebrating its 20th anniversary this summer – as the show first premiered on FX in the summer of 2005. Author Kimberly Potts’ new book out July 1, “It’s (Almost) Always Sunny in Philadelphia: How Three Friends Spent $200 to Create the Longest-Running Live-Action Sitcom in History and Help Build a Network,” details the show’s unlikely rise to prominence and behind the scenes stories. Potts, who has also written a book about “The Brady Bunch,” told The Post that during her research she learned how Danny DeVito nearly died while filming the series. During the Season 11 episode “The Gang Goes to Hell: Part Two,” the group is on a cruise, and are trapped in a room that has a leak.The episode aired on March 9, 2016.“They’re swimming, they keep rising to the top.

And to shoot that scene, they were underwater,” Potts explained, noting that the water level is rising.“At one point, Danny got accidentally kicked, I think, in the shoulder –- close to his head.As I’ve been told, he nearly drowned,” she added.

“It certainly had everyone afraid he was in trouble.” Created by Rob McElhenney and co-developed by Glenn Howerton, the show follows a group of narcissist and sociopathic friends who own a pub in the titular city: Dennis (Howerton), Charlie (Charlie Day), Mac (McElhenney), Dee (Kaitlin Olson), and Dennis and Dee’s father, Frank (Danny DeVito). After they rescued DeVito, “he was very frustrated by that situation,” Potts recalled to The Post.“He just quietly left, and the day was over for him.

So even he has a threshold for how far he’s willing to go.But for the overwhelming majority, their experience with him is great,” she acknowledged.

“Kaitlin Olson has called him the happiest person she’s ever known.”Potts’ book details the show’s unlikely success story, as the comedy’s original pilot cost Day, Howert...