The Oscar winner will play one of the judges in a March episode of the Fox musical.

Glee's Nationals episode is starting to take shape.

After booking Pitch Perfect star Skylar Astin to compete with New Directions, the Fox musical has added a judge for the competition.

Oscar winner Marlee Matlin (Children of a Lesser God) has boarded Glee as a judge, guest starring in a March episode, The Hollywood Reporter has confirmed.

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Matlin, who co-stars on ABC Family's Switched at Birth, first teased her role with Glee on Twitter, posting that she was spending the next few days filming the musical dramedy and sharing a photo (above) with Astin (Jean-Baptiste), Darren Criss (Blaine) and Chord Overstreet (Sam).

Matlin, who will play herself, becomes the latest actor to appear as a judge on the Fox series, joining Lindsay Lohan, Perez Hilton, Kathy Griffin and Loretta Devine. Additional judges are expected to be announced.

Glee returns on its new night and time Feb. 25 on Fox.

Email: Lesley.Goldberg@THR.com

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