CBS' Under the Dome is staging another ER reunion.

Executive producer/showrunner Neal Baer has recruited former ER alum Sherry Stringfield for a major role in the second season of the CBS summer drama, The Hollywood Reporter has learned.

Stringfield will have a recurring guest role and play the meaty role of Pauline, a mysterious woman who may be connected to the origins of the dome. A character with the same name -- Pauline Rennie -- exists in the Stephen King book on which the drama is based. She's the late wife of "Big Jim" Rennie -- played on the CBS show by Dean Norris -- and Junior's mother (Alexander Koch). It's unclear if the character on CBS' adaptation is one and the same as the series has taken several detours from King's best-seller.

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"I'm thrilled after all these years to be working again with Sherry Stringfield. We had a blast on ER together and I know Sherry will bring the same grace, spirit and intensity to her new, pivotal role on Under the Dome," Baer said in a statement to THR. Stringfield is Dome's second ER alum to board the series after Mare Winningham guest starred in season one.

Stringfield played fan favorite Dr. Susan Lewis on NBC's long-running medical drama, which Baer was an exec producer on. More recently, her credits include episodes of CSI and TV movies including The Confession and Hornet's Nest. She's repped by Jason Shapiro.

The actress becomes the latest addition to Dome's second season. The series, which is poised to kill off two "favorites" when it returns with its King-penned season-two premiere June 30, has also added CSI: NY's Eddie Cahill as Big Jim's brother-in-law Sam; Misfits' Karla Crome as Rebecca, a teacher; and newcomer Grace Victoria Cox as Melanie, a potential love interest for Joe (Colin Ford).

Email: Lesley.Goldberg@THR.com
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