Neve Campbell stopped by Seattle Grace in “Love Turns You Upside Down,” the latest episode of ABC’s smash hit medical drama Grey’s Anatomy, now in its ninth season.

Campbell guest-starred as Lizzie Shepherd, one of McDreamy’s…err…Derek Shepherd’s (Patrick Dempsey) sisters. Derek, who has been dealing with an injured hand, needed a nerve transplant to have any hope of resuming his surgical career, and the best plan of action was to obtain a live-nerve from a family member. Derek was against the idea because he didn’t want his family involved; however, after Meredith (Ellen Pompeo) encouraged Heather (Tina Majorino), Heather phoned Derek’s sisters in the hopes that one would return the call. Fortunately one, Lizzie, did.

Lizze marks the third Shepherd sister to enter the show, after Amelia (Caterina Scorsone) and Nancy (Embeth Davidtz).

Aside from Grey's Anatomy, Campbell recently appeared in Titanic: Blood & Steel, a 12-part miniseries for CBC, and 2011’s Scream 4. Campbell and Dempsey had previously worked together on Scream 3. "It's funny because we played sort of pseudo-love interests in 'Scream' years ago,” Campbell told HuffPost TV. “Not weird at all."

Campbell will be on the Grey’s set for at least one more episode as her character said she wanted to stay through Derek’s surgery. Grey’s Anatomy airs on ABC Thursdays at 9 p.m. EST.

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