NEW YORK, NY - MAY 20: Actress Lily Rabe attends the 2011 Drama League Awards ceremony and luncheon at Marriot Marquis on May 20, 2011 in New York City.

She becomes the fourth person cast in the FX anthology, joining Jessica Lange, Sarah Paulson and Evan Peters.

Good news for American Horror Story fans.

Co-star Lily Rabe apparently has signed on for the mysterious third season of the FX anthology series, according to Ryan Murphy.

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The co-creator of the miniseries that reboots itself with familiar faces playing different characters each year shared the news late Thursday on Twitter: "So thrilled to announce Lily Rabe is onboard for American Horror Story Season Three! So talented, love her!" he wrote.

The actress becomes the fourth person cast, joining Jessica Lange, Sarah Paulson and Evan Peters -- all of whom will have appeared in all three seasons.

After a smallish role as a ghost in season one, Rabe broke out in the sophomore season playing Sister Mary Eunice -- a power-hungry nun possessed by the devil who roamed Briarcliff.

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"I will say that for season three, we are going to have some actors from season one who will return," Murphy told reporters after a screening of the season two finale in mid-January. "I like that idea. I know that those actors are interested in that."

While details on season three are, again, being kept under wraps, the showrunner has hinted that it would be a modern-day story revolving around Lange. "We do have a great icon, and it's a woman," he said, noting that the show again would be inspired by things that he's personally interested in.

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After two seasons of death and (literal) insanity, the Glee and New Normal co-creator also said AHS would explore familiar themes. "What season three is about is more historical in nature," he teased. "I'm also interested in getting into a horror romance. That's certainly something that's going to be in the water for season three.

Season one co-star Taissa Farmiga also reportedly is circling a return after sitting out the sophomore year of AHS.

Rabe is repped by ICM Partners, Framework and Schreck Rose.

Email: Lesley.Goldberg@thr.com; Twitter: @Snoodit