In the gallery below, check out Leslie Knope (Amy Poehler) as Rosie the Riveter and Ann Perkins (Rashida Jones) as an Olympian in the Season 5 episode "Halloween Surprise." Plus, "The Office" continues its Halloween tradition in Season 9's "Here Comes Treble."
"Up All Night," "Go On," "The New Normal" and "Guys With Kids" are also getting into the Halloween spirit. Click through the slideshow below to see all the pictures.
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