'Grey's Anatomy' season 12 spoilers: Meredith is again reminded of Derek's death in episode 5

Meredith looks troubled as she recognizes the doctor who failed to save Derek, on Grey's Anatomy Youtube screenshot/ file

This week on "Grey's Anatomy," Meredith will be reminded once again of Derek's death when someone from the past shows up at her dinner party.

In the sneak peek for the episode titled "Guess Who's Coming to Dinner," the scene picks up where it left off last week, at Meredith, Maggie, and Amelia's dinner party. Callie arrives with her new girlfriend, Penny, who happens to be one of the doctors who couldn't save Derek's life. Meredith recognizes her and is reminded of Derek's death, and she tries to shake it off while everyone else in the house introduced themselves to Penny.

April goes to Penny to introduce herself, and Meredith watches the interaction with a pained look on her face as she keeps her hands on top of a blender.

"Kepner's on trauma," Callie tells Penny as April walks away. Callie tries to explain April's situation with Jackson, as she continues, "Her husband is on plastics, although, maybe not her husband…We don't know. They might not know." She adds that Jackson's family owns the place, but reassures her that it's "not nepotism, he's great."

"At last, we get to meet the legendary Penny!" Amelia exclaims while handing the newcomer a drink. "Whatever she tells you about us, just ignore it," she quips while giving Penny a hug, much to Penny's mingled surprise and pleasure at her warm welcome.

Penny appears to notice Meredith staring at her as she furtively glances at Meredith while Amelia is talking to her and Callie.

"Amelia's chief of neuro…a little volatile, but outstanding," Callie whispers to her new girlfriend.

Alex notices that something is amiss with Meredith, as he gets her to turn off the blender and he asks her what's going on. Meredith replies that she's great, but Alex seems to think otherwise.

"You're not great, you're freaked out, you're smiling a lot," he points out. Alex added that Meredith is acting as if she's in a hostage video and insists that something is wrong.

Meredith is at a loss for words, and on Thursday, viewers will get to see whether she'll tell everyone how she knows Penny's girlfriend and the circumstances that led to their initial meeting.

"Grey's Anatomy" airs on Thursdays at 8 p.m. on ABC.

News
Sarah Mullally reiterates apology as safeguarding record comes under the spotlight
Sarah Mullally reiterates apology as safeguarding record comes under the spotlight

The incoming Archbishop of Canterbury, Sarah Mullally, has come under pressure over her handling of past safeguarding cases. 

Evangelical vicar accused of abuse won't stand trial
Evangelical vicar accused of abuse won't stand trial

A leading figure among conservative evangelical Anglicans will not stand trial for alleged abuse, it has emerged.

Church of England bishops delay final decision on same-sex blessings
Church of England bishops delay final decision on same-sex blessings

The Church of England's House of Bishops has postponed a final decision on the Living in Love and Faith process as it continues to work on proposals. 

Faith in the festive chaos: how you can sustain your family’s faith this Christmas
Faith in the festive chaos: how you can sustain your family’s faith this Christmas

Anna Hawken, Parenting for Faith from BRF Ministries, has some helpful tips for families to connect with God in the midst of the "December tornado".