As first reported by TVLine.com, Swallow will make her debut in the Dec. 1 episode as Kim Fischer, a mysterious woman who will have an influence on Jane's life.
With the impending exits of Amanda Righetti and Owain Yeoman, Swallow isn't the only newbie promoted to series regular. Rockmond Dunbar, who will play FBI Supervisory Agent Dennis Abbott beginning in Sunday's episode, was also recently promoted.
The Mentalist airs Sundays at 10/9c on CBS.
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