The number of episodes in which Preston will appear is unclear. In 2013, she won an Emmy for Outstanding Guest Actress in a Drama Series for playing Elsbeth.
With True Blood's series finale fast approaching, Preston tells Entertainment Weekly she's hoping to land another series regular gig on a different show.
The Good Wife returns Sunday, Sept. 21 at 9/8c on CBS.
(Full disclosure: TVGuide.com is owned by CBS.)
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