'Grey's Anatomy': See How Meredith Responds to Callie's New Girlfriend

Also known as the doctor who killed Derek.
James DePietro/Courtesy of SDB Partners
Samantha Sloyan

A key player in Derek's (Patrick Dempsey) death is returning to Grey's Anatomy.

Samantha Sloyan is returning to reprise her role as Penny — Callie's new girlfriend — during Thursday's landmark 250th episode of the ABC medical drama from Shonda Rhimes and Betsy Beers.

In the clip below from the episode "Guess Who's Coming to Dinner?" Meredith is flooded by memories of the worst day of her life — the day that Penny told her she wasn't able to save her husband.

Sloyan first appeared in the April 23 installment in which Dempsey's beloved Derek was involved in an ultimately fatal car crash. Sloyan played a doctor at the Dillard Medical Center who — despite her best efforts — ultimately was unable to save his life. The doctor, who was outside the hospital crying, had a memorable exchange Meredith (Ellen Pompeo), who said that Derek's was the face the young surgeon would see every time she treats a patient. Mer indicated the experience would either make Sloyan's character a better doctor or she'd quit and then encouraged the young surgeon to head back inside to save lives.

Showrunner Rhimes told THR last month that both Callie and Arizona would have new (female) love interests in season 12. "That felt natural and it's what the story is about and how it plays out. I really tried to stay true to the idea that she's bisexual but it's literally what the story is."

Said Ramirez of the storyline: "She's exploring new love and it's a hot dating situation and there's some unexpected twists and turns as always. They do it brilliantly and it's in a way that affects a lot of people."

Sloyan's arrival at Grey Sloan Memorial sets up an interesting storyline for Meredith, as well as for Mer and Callie.

Fun fact: This is Sloyan's second visit to Shondaland. She previously played Fitz's (Tony Goldwyn) faux-mistress during Scandal's third season.