US TV
The Party Down star will play Leslie Knope's (Amy Poehler) new love interest, reports Variety.
"Adam is one of the funniest and most versatile performers around," said show executive producer Michael Schur.
He added: "When we designed the character he is going to play, we used him as the dream scenario of who we could get."
Scott is to appear on the final two episodes of the current season and join next season as a regular.
The 36-year-old has also appeared in the films Leap Year, Step Brothers and Knocked Up.
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