Sara Ramirez, <em>Grey's Anatomy</em> Sara Ramirez, Grey's Anatomy

[Warning: This article contains spoilers about Thursday's episode of Grey's Anatomy. Read at your own risk!]

Well, well, well ... Grey's Anatomy still has a few tricks up its sleeve in Season 12.

At the end of Thursday's episode, at a much-hyped dinner party thrown by Amelia (Caterina Scorsone), Meredith (Ellen Pompeo) and Maggie (Kelly McCreary) - who is absent, because she's back at the hospital hooking up again with hot intern Andrew (Giacomo Giannioti) - we finally get to meet Callie's (Sara Ramirez) new girlfriend, Penny.

Arizona (Jessica Capshaw) drains her glass of wine in anticipation of the inevitably tense introduction, but it's actually Meredith whose jaw drops when she opens the door and sees Callie's companion. Turns out, Penny is the doctor who could have saved Derek's life last season, had she not botched his care when he was brought to the hospital.

Jaw, meet floor. This is going to be awkward.

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Other highlights of the episode:

-April (Sarah Drew) refuses to accept Jackson's (Jesse Williams) demand for a divorce, telling Arizona that she has no interest in finding new love because she's already met her soulmate.

-Stephanie (Jerrika Hinton) is getting physically ill because of the intense treatment Amelia is forcing her to give a patient named Rachel, who is recovering from brain surgery. We find out that Stephanie is having such a tough time because when she was 5 years old, she was a patient in a sickle cell anemia trial, and is still scarred from the poking and prodding she received "for her own good."

-Jo (Camilla Luddington), believing that Stephanie made up the whole sickle cell anemia story, rats her out to Amelia - who discovers Stephanie was telling the truth only after she tries to report her to Webber. In actuality, Stephanie just doesn't like to talk about her stint as a patient, and the side-eye she shoots Jo at the dinner party later is almost as threatening as her (false) admission that she doesn't have a conscience earlier in the episode - which led me to seriously wonder whether Stephanie could be an actual sociopath. Props, Jerrika Hinton.

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-As the hospital deals with a "silver flood," aka an influx of elderly patients, who were involved in a bus accident, the newbies get a harsh lesson in breaking bad news to the families of patients who have died. Owen (Kevin McKidd) initially tries to train them, but later Meredith takes the lead, having been on the receiving end of that conversation fairly recently. Her speech about the important role doctors play when relaying this information becomes especially poignant minutes later, when Penny's arrival at her house sparks flashbacks to the day Derek died.

-While Maggie is having her own flashbacks, of the sex variety, Meredith realizes that she hasn't thought about sex since the morning Derek died. "That part of my life is over," she says, and later swears to Maggie (seemingly sincerely) that she's perfectly content being on her own and has no interest in looking for love. Do we think this will last?

What do you think, Grey's fans? Were you shocked by the twist with Penny? Do you really think Meredith will never look for love again? Do you like Maggie and Andrew together? And how uncomfortable is that dinner party going to be next week? Sound off in the comments!

Grey's Anatomy airs Thursdays at 8/7c on ABC.

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