9. "Greg Pikitis," Parks and Recreation
Air Date: 10/29/09
Like many sitcoms, Parks & Rec didn't truly find its footing until its second season, which includes instant gems like this Halloween episode that pits Leslie (Amy Poehler) against her arch-nemesis: the eponymous Greg Pikitis (Cody Klop), whom she knows is responsible for the annual vandalizing of the town's statue of Mayor Percy, but has never been able to prove it.
With the help of Andy (Chris Pratt) and her cop boyfriend Dave (guest star Louis C.K.), she makes it her night's mission to outwit Greg before he can get to the statue, but the young delinquent has a few tricks up his sleeve. Elsewhere a T-Pain clad Tom (Aziz Ansari) turns up Ann's (Rashida Jones) costume party while Ron F*cking Swanson (Nick Offerman) ponders moving in on his green-card-marriage wife.