Bart learns of a legendary prankster (voice of Jonah Hill) from Springfield Elementary's past and becomes fast Friends with the joker, who's now 19 years old and hasn't stopped doing pranks.
The Simpsons travel to Ireland so that Grandpa can have one last bière at his beloved O'Flanagan's Pub in Dunkilderry, but it's not the quaint Irish town Grandpa remembers.