Exclusive: Justin Theroux joins 'Parks and Recreation'

Actor-producer-screenwriter-all-around Renaissance man Justin Theroux is joining Parks and Recreation (a.k.a. this fall’s most improved comedy) in a major recurring role, sources confirm to me exclusively.

Theroux, whose previous tube work includes stints on The District, Ally McBeal, and Sex and the City, has been cast as a friend of Ann’s (Rashida Jones) and a potential love interest for Leslie (Amy Poehler). His first episode is slated to air in early 2010.

Last month it was announced that Theroux had signed on to produce a big-screen comedy for Paramount set in the world of air guitar competitions. He also wrote the screenplays for Tropic Thunder and the upcoming Iron Man 2. And played everyone from Jesus Christ to John Hancock. A one-trick pony he’s not.

PHOTO REQUEST: Theroux: Sara De Boer/Retna Ltd.; Poehler: NBC