'Grey's Anatomy' : Derek Returns as the Doctors of Grey Sloan Mourn the Loss of One of Their Own

Patrick Dempsey reprised his role as the late Derek Shepherd for the third time this season during Thursday’s episode of Grey’s Anatomy 

This post contains spoilers from Thursday's episode of Grey's Anatomy.

Grey's Anatomy remains somber as the doctors of Grey Sloan Memorial mourn the loss of one of their own — but good news may be on the horizon for Meredith Grey's COVID battle.

In last week's two-hour crossover mid-season premiere with Station 19, the doctors fought hard to save the life of Dr. Andrew DeLuca (Giacomo Gianniotti), who was stabbed in his attempt to pursue and expose a sex trafficker. Things quickly took a turn after an emergency surgery, and DeLuca died on the operating table.

Thursday's episode showed the aftermath of his death, with Dr. Richard Webber (James Pickens Jr.) seeking comfort from wife Catherine Avery (Debbie Allen), Owen Hunt (Kevin McKidd) packing away DeLuca's ID badge and Levi Schmitt (Jake Borelli) recording a video tribute for the late doctor for a virtual funeral amid the COVID-19 pandemic.

Teddy Altman (Kim Raver) cared for Meredith (Ellen Pompeo) as she continued to face her own severe case of COVID-19. Teddy, unraveling in the wake of DeLuca's death, thought she saw DeLuca appear to her, only to realize that she was imagining things, and pediatric surgeon Dr. Cormac Hayes (Richard Flood) was standing in front of her instead.

Ali Goldstein/abc

Chief of Surgery Miranda Bailey (Chandra Wilson) handled her grief in her usual way, by seeking more answers.

"I expect DeLuca's autopsy results by the end of the day," Bailey told a group of doctors, including DeLuca's surgeon, Teddy, who replied, "You asked for his results? Why?"

"Andrew DeLuca was one of our own," Bailey explained. "Obviously something went wrong — I want to know what that was."

"I already told you every step of what happened," Richard argued, but Bailey insisted that he didn't tell her until "well after I could have done something to change the outcome."

Giacomo Gianniotti as Andrew DeLuca. Gilles Mingasson/ABC via Getty Images

Meanwhile, Meredith's late husband Derek Shepherd (Patrick Dempsey) made his third surprise appearance of the season as Meredith — sedated and on a ventilator — continued to experience dream sequences set on an idyllic beach.

"You looked just like Ellis just now, the way you're looking at your feet, so serious, and she gives that worrying little brow," Derek told Meredith, discussing their youngest child, daughter Ellis, who was born after Derek's death.

"This is torture," Meredith replied, to which he said, "It's a torture of your own devising — you're always good at that."

Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories.

"You never got to meet Ellis. We didn't even know, I wish you got to know her," Meredith later told her husband.

"She looks just like you," Derek gushed of his daughter. "She breaks the rules just like you. And she's quick to anger, and quick to laugh. She's smart, gifted, stubborn, just like you. Hates pink and purple, loves brown and green and gets enraged at the thought of anybody wanting to cut down a tree."

Back at Grey Sloan, Bailey and Richard continued to argue about whether or not to look deeper into DeLuca's death, ultimately realizing that the doctors did everything they could to save him. Bailey later decided to take some time off from the hospital, asking the always-willing Richard to step into her place.

Patrick Dempsey in Grey's Anatomy. ABC

And then back to the beach. Meredith begged her vision of Derek to come "closer" as Derek went on discussing their children — perhaps foreshadowing that Meredith would be reunited with them soon.

"You remember when you were trying to teach Zola how to ride a bike?" Derek asked. "She got so frustrated ... she threw it down and she goes, 'Mama, you do it!' And she got so mad."

"Well, I was trying not to laugh," Meredith said, and Derek perplexingly replied, "So am I."

"I can't do it for you," he continued. "It's your beach. Zola is amazing, isn't she? She's just so brilliant. She writes me letters in her journal — did you know that?"

As Dr. Hayes looked after Meredith at the hospital, her dream sequence began to merge with reality for the first time.

Patrick Dempsey and Ellen Pompeo. Krista Vernoff/abc

Hayes begged Meredith to "fight" as he discussed how her kids video chatted her while she has been sedated, and Derek, still on the beach, advised Meredith to "hear him out."

Hayes then entered Meredith's vision. "They need you to fight," he said as they walked along the beach, referencing her kids. "We all need you to fight."

"I don't know that I can," she said. "It's so warm here. The water is so cool. I feel so relaxed. And there's no pain."

"I watched my kids lose their mom, you don't want that for your kids, Grey," he replied. "There are people getting better here — you could be one of those people."

"I believe that you could, because I've heard the stories about all the fights you've already won, so I'm asking you to fight," Hayes continued, as Derek assured her, "It's okay. I'll be right here."

Grey's Anatomy airs Thursdays (9 p.m. ET) on ABC.