The news comes on the heels of Williams' much-hyped return to the Miss America pageant earlier this month.
Additional details about Williams' characters have not been made public. She joins previously-announced new additions Jeffrey Dean Morgan, who's playing an investigator who works for Alicia (Julianna Margulies), and Margo Martindale, who will portray a campaign operative who works for Peter (Chris Noth).
The Good Wife returns Sunday, Oct. 4 at 10/9c on CBS.
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