Parker Posey, Alan Cumming

The Good Wife is adding to its already impressive guest star roster for Season 3.

The CBS legal drama has cast Parker Posey to play the estranged wife of campaign manager Eli Gold (Alan Cumming), a show rep confirms. Posey, who will begin her Big C arc on Monday, will appear in an episode airing in October, according to TVLine, which first reported her casting.

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Viewers first met the fictional couple's teenage daughter, Marissa (played by Sarah Steele) last season.

House's Peter Jacobson will also be stopping by The Good Wife for the Season 3 premiere, CBS announced Thursday. Jacobson's appearance follows the series' casting of his former House castmate, Lisa Edelstein, who will appear in a multi-episode arc this season. Their guest spots will not overlap.

Posey and Jacobson join previously announced guest stars including Eddie Izzard, Harvey Fierstein and a return appearance from Kelli Giddish.

Watch the new Season 3 preview — Alicia rocks bangs! -- for The Good Wife:

The Good Wife returns on Sunday, Sept. 25 at 9/8c on CBS.