Buono, who was nominated for an Emmy for her performance as Dr. Faye Miller on Mad Men, will play a femme fatale on the CBS drama. Season 4 of the show will follow a "new world order," in which Reese (Jim Caviezel), Finch (Michael Emerson) and the rest of the crew are forced to use aliases to hide from the omnipresent Samaritan. Buono's character is "uniquely qualified" to navigate the new circumstances, according to Deadline, which first reported the news.
Person of Interest returns Tuesday, Sept. 23 at 10/9c on CBS.
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