Former Numb3rs  actress Diane Farr will appear on Grey's Anatomy this season, according to a show rep.

The 40-year-old actress will play a patient with Huntington's Disease under the care of Meredith (Ellen Pompeo). Farr is slated to appear in the fourth episode of the season, which will air sometime in October.

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The casting was first reported by Entertainment Weekly.

Farr, also known for her work on Rescue Me, guest-starred in an episode of White Collar earlier this month.

Grey's Anatomy returns for its seventh season Thursday, Sept. 23 at 9/8c on ABC.