It's Always Sunny in Philadelphia S15E07 - Dee Sinks in a Bog

Guided by a young priest, Mac spends a day at the seminary to truly understand what it takes to become a priest. Dennis and Frank plan an elaborate trap at the castle to humiliate Charlie's pen pal. Dee prepares for a date with an Irish doctor, only to find herself sinking in a bog. Having learned of his pen pal's true identity, Charlie bonds with him and makes a choice that will forever change the Gang.