Credit: Video Still

In the Canadian promo for Grey's Anatomy Season 9, Episode 8: “Love Turns You Upside Down” (airing December 6), the interns finally get some weightier storylines. And Derek’s (Patrick Dempsey) sister (played by a fantastic-looking Neve Campbell) does not seem like the nicest person.

After an incoming case involving Bigfoot and the men who apparently ran “him” over sends Seattle Grace-Mercy West into comedic chaos, Derek’s sis shows up looking pristine, calm, and self-assured. And then she’s mean to an intern.

What will she say about Derek and Meredith’s (Ellen Pompeo) new bun in the oven? Check out the preview below!

Credit: SpoilerTV Photo: Grey’s Anatomy Season 9, Episode 8 Canadian Promo: Who Shot Bigfoot? (VIDEO)

For more Grey’s spoilers, click here.

Catch the next new episode of Grey’s Anatomy on Thursday, December 6 at 9 p.m. ET/PT on ABC.

Molly Friedman is an editor at Wetpaint Entertainment. Follow her on Twitter @MollyFriedman.

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