Kelli Williams

The Mentalist's Patrick Jane is about to get a (perhaps unwanted) blast from the past.

Former Lie to Me and The Practice star Kelli Williams will guest-star on the CBS drama's upcoming fourth season, TVGuide.com has learned exclusively. She will play Beth Flint, a woman who once hired Jane (Simon Baker) during his days as a pretend psychic.

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"She still believes he has psychic powers," creator and executive producer Bruno Heller tells us. "When her 9-year-old son, Connor, is kidnapped, she begs Jane to use those abilities to find Connor, putting Jane in a painful position."

Williams' casting follows the news that former Melrose Place star Michael Rady will recur this season as the new CBI Boss. Other guest stars this season include Reed Diamond, who will play a CBI agent who assists Lisbon (Robin Tunney) and her team with an investigation.

The Mentalist hires Michael Rady to play Patrick Jane's new boss

Williams, 41, is best known for her work as Lindsay Dole on The Practice and most recently as Dr. Gillian Foster on Fox's Lie to Me. She has also appeared on Scrubs, Men in Trees and Criminal Minds.

The Mentalist's fourth season kicks off Thursday, Sept. 22 at 10/9c on CBS. Williams' episode is slated to air Oct. 6.