Jonny Lee Miller Jonny Lee Miller

Jane Alexander will guest-star in an upcoming episode of Elementary, executive producer Rob Doherty announced at the Television Critics Association winter press tour on Wednesday.

Alexander will play C, a pen pal of Sherlock's (Jonny Lee Miller) whom he turns to for help with a case. "She and Sherlock have been engaged in a certain brand correspondence for the past few years," Doherty tells "They trade erotic letters. They've never met face-to-face, but they will in the episode in which Jane appears. She works in antiquities, and Sherlock believes she may be able to help with a case that he and Joan [Lucy Liu] are investigating."

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The four-time Oscar nominee's recent television credits include The Blacklist and The Good Wife.

Elementary airs Thursdays at 10/9c on CBS.

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