'Parks and Recreation': Patricia Clarkson Debuts As Ron Swanson's Ex (Video)

If viewers thought Tammy II (Megan Mullally) was scary with her aggressive sexual advances and manipulating ways, they will not know what hit them when Tammy I appears in the new season of Parks and Recreation.

A new promo for the NBC comedy introduces Tammy I, played by Patricia Clarkson. As the first ex-wife of Ron Swanson (Nick Offerman), she returns to Pawnee, and messes with Ron’s head.

STORY: 'Parks and Recreation' Reveals Tammy 1: Patricia Clarkson

"Tammy One and Tammy Two could not be anymore different," Offerman says. "Tammy Two, played by my wife Megan is a raging hellcat who uses her sexual wiles to control Ron."

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“Tammy One is ice cold, dangerous, steely and maternal," says Amy Poehler, who plays Leslie Knope on the show. “She comes in and pushes Ron away in a way we haven't seen before. Ron gets neutered and turns into basically an infant."

“It’s the creepiest thing that’s happened to Ron, and we’ve seen Ron in corn rows.”

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Patricia Clarkson won two Emmys for her guet role on Six Feet Under and was nominated for an Oscar for her performance in Pieces of April. She also played the mother of Justin Timberlake’s character on the SNL skit “Motherlover.”

Parks and Recreation returns on September 22.