Grey's Anatomy Season 9 delivers a new episode Thursday night on U.S. television: Episode 8 is called, "Love Turns You Upside Down." The character played by guest star Neve Campbell debuts in this episode. Is she a good news or bad news to the Mer-Der couple?

Meanwhile, interns are expected to show off and prove their worth to Seattle Grace Mercy West. The episode's official summary says:

"The new batch of interns find themselves involved in all the drama at Seattle Grace: Meredith asks Heather to go above and beyond to help fix Derek's hand; Cristina starts a healthy competition between Stephanie and Leah, which inadvertently leads to a medical emergency for Cristina's patient; Alex sees Jo in a new light as they work to save a baby's life, and April teaches Shane a valuable lesson during 'lumps and bumps' duty."

Neve Campbell as Derek's Sis Liz Shepherd -- Will She Stir Some Trouble?

Another one of Derek's sisters is showing up for the first time, and her role will be played by Neve Campbell. Does she mean well?

Grey's Anatomy Season 9: Neve Campbell Checks-In as Dr. Liz Shepherd

Derek's sister will give her prized surgeon brother a key element in his hand surgery. So that should be good news.

HuffPost TV reported Derek will "need to have nerves transplanted from a blood relative for the best shot at fully healing." But wait. Will Liz make things easy for her brother's pregnant wife?

Asked to describe Liz, Campbell she is "quite outspoken and quite ballsy and very forthright with her feelings about other people's lives." Okay then, watch out, Meredith.

Campbell, who starred with Dempsey in "Scream 3" in 1999, hinted she had a good time filming her multi-episode appearance in the hit ABC medical drama.

"It was fun to be around a group that had been working together so long," she told TV Line.

The rise of the interns: Who is the star player in this week's episode?

The interns will be central players in this week's episode of Grey's Anatomy based on the sneak peek video released by ABC.

"School's in session. And some lessons have to be learned the hard way," the promo video says.

Gather.com reported, "Meredith enlists intern Heather to find a way to help fix Derek's hand, and that means the intern is going to end up a bit caught in the middle-and in a place she'd rather not be."

VIDEO CLIP: Grey's Anatomy Season 9 Episode 8

For a sneak peek at Grey's Anatomy Season 9 Episode 8: "Love Turns You Upside Down," OfficialTVPromos posted this video to YouTube:

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