"Entourage" star Constance Zimmerman will make multiple appearances on the ABC series "Grey's Anatomy" once it returns from its winter hiatus and when asked via Twitter if fans will like her character, the actress replied with a tentative "Not sure." 

Zimmerman will debut in the series starting with episode 12 in which she will play Dr. Cahill, "a confident, self-possessed and laser-focused professional with a wicked sense of humor." The once arch-rival of Ari Gold in the now cancelled HBO series, Zimmerman will be in Seattle Grace for at least four episodes.

The actress recently guest starred on NBC's "The New Normal" and has a major role in David Fincher's upcoming drama "House of Cards." Zimmerman joins new cast members Neve Campbell, who plays Derek Shepard's sister, and Dominic Hoffman who plays Dr. Jeff Russell.

The newest episode of "Grey's Anatomy" is episode 10, "The Things We Said Today," which airs Thursday, Jan. 10, at 9 p.m. ET.

So far spoilers for the remainder of season nine have revealed that a familiar face will die on the show. Before "Grey's" went on its winter break, Bailey and Richard were seen at the hospital (choosing to skip Bailey's wedding) in episode nine to care for Adele who was admitted at Seattle Grace for vomiting blood.

Though from the coughing of blood it might have already been assumed by many, Adele is confirmed to die and will not be on the show past January. Loretta Devine told TV Guide that her final scenes were extremely "painful" to film, hinting to the fact that she may not simply die on the operating table. 

Devine leaving the show could be because she has a major role in the Lifetime television series "The Client List," which also stars Jennifer Love Hewitt. The show was picked up for a second season and will air Sunday nights in 2013.

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