The Gang Goes to Ireland

"The Gang Goes to Ireland" is the fifth episode of the fifteenth season of It's Always Sunny in Philadelphia.

Synopsis
The Gang's in Dublin! Dennis longs for a charming, authentic European experience, but ends up helping Frank with some of his business's "dirty work." Mac and Charlie learn about their Irish heritage. Dee rushes to the set of an Irish soap opera, where she will play the role of "Obnoxious American MILF."

Starring

 * Charlie Day as Charlie Kelly
 * Glenn Howerton as Dennis Reynolds
 * Rob McElhenney as Mac
 * Kaitlin Olson as Dee Reynolds
 * Danny DeVito as Frank Reynolds

Guest Starring

 * Mary Elizabeth Ellis as The Waitress
 * Sandy Martin as Mrs. Mac

Co-Starring

 * Sam Lucas Smith as Conor
 * Kemma Filby as Bartender

Trivia

 * Charlie has evidently patched the holes in his green jacket, which was shown to still be ripped up in the season premiere.