First Look: Megan Mullally Stays 'Up All Night'

With recurring roles on Parks & Recreation, Happy Endings and Breaking In, Emmy-winner Megan Mullally is the busiest woman in television -- and she's adding one more sensational show on Thursday when she guest-stars on Up All Night!

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In the episode, titled Rivals, Mullally plays Shayna -- Ava's talk show nemesis, who used to be considered a "friend of the show." Shayna comes back into Regan & Ava's world when they accuse her of stealing their show ideas

ETonline is pleased to present an exclusive first look at Thursday's episode, where the former Will & Grace star adds another amazing character into her ever-elongating repertoire.

Up All Night airs Thursdays at 9:30 p.m. on NBC.