‘Under the Dome’ Books Mare Winningham

Emmy winner and Oscar nominee Mare Winningham is moving under CBS' Dome.

The actress has booked a mysterious role on CBS' sci-fi drama Under the Dome, The Hollywood Reporter has learned.

The drama, which premiered last week to more than 13 million viewers, revolves around the residents of Chester's Mill and what happens when a mysterious dome suddenly seals the town off from the rest of the world.

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Winningham will guest star in an episode of the Stephen King adaptation slated to air in late August as Agatha, a seemingly warm woman who is serving as a caretaker for one of the houses under the dome. Agatha welcomes the town's leader Big Jim (Breaking Bad's Dean Norris) into the home but we soon learn that her intentions are anything but sincere as her ties to Chester's Mill soon surface.

The casting marks a reunion for the actress with Dome showrunner Neal Baer.

"I'm thrilled to be working with Mare Winningham on Under the Dome," Baer said. "She's my good-luck charm: I worked with her on ER, as well as on Law & Order: SVU -- for which she was Emmy-nominated as best guest actress. She brings truth and believability to every role and she will definitely leave viewers talking."

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Winningham earned an Oscar nomination in 1995 for her supporting turn in Georgia. She's a two-time Emmy winner for supporting turns in George Wallace and Amber Waves, and earned nominations for History's Hatfields & McCoys, HBO's Mildred Pierce as well as SVU, The Boys Next Door and Love Is Never Silent.

She's repped by IFA and Margrit Polak.

Under the Dome airs Mondays at 10 p.m. on CBS.

E-mail: Lesley.Goldberg@thr.com
Twitter: @Snoodit

Lesley Goldberg