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Jason Ritter and Kristen Schaal star as animated twins in the new Disney Channel series Gravity Falls and veteran comedian Jennifer Coolidge is guest starring on this week's episode. ETonline has an exclusive first look!

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Currently known for his role on the comedy-drama series Parenthood, Ritter plays "Dipper Pines," a smart and zealous boy who was born for adventure, in his first voice acting project. Kristen Schaal, the voice of Ritter's on-screen twin, plays "Mabel Pines," an outgoing, energetic girl who always sees the glass half-full. Unlike the voice actor of her animated twin, Schaal is a veteran in voicing animated characters, and currently has a role on the animated sitcom Bob's Burgers. Coolidge plays a character named "Lazy Susan" in the series.

Check out the clip above of this week's Gravity Falls, set to air on Friday, July 20 at 9:30 p.m. on Disney Channel.