'Grey's Anatomy' : Tom Koracick Arrives in Minnesota as 'Station 19' Loses a Fan-Favorite Firefighter

Thursday's episode marked a heartbreaking crossover with Shondaland's Station 19

Ellen Pompeo, Peter Gallagher. Photo: Bonnie Osborne/ABC

This week's episode of Grey's Anatomy was part of another crossover with Station 19.

The doctors of Grey Sloan Memorial were inundated with trauma cases after two residential gas explosions left several people — including firefighters — injured in a mass casualty event.

Grey's picked up in the aftermath of the explosions that took place in Station 19 and led to an influx of patients at the hospital — and to an injury for firefighter Victoria "Vic" Hughes (Barrett Doss) and the shocking death of Dean Miller (Okieriete Onaodowan).

Dr. Miranda Bailey (Chandra Wilson) — worried about husband Ben Warren — is first to get a patient from the disaster. The first patient to arrive at Grey Sloan is Vic, who deadpans to Bailey, "Hi, I almost died."

As Bailey is attending to Vic and learning what happened — a gas leak was caused by construction — Dr. Richard Webber (James Pickens Jr.) comes in to tell her that more casualties are en route to the hospital.

Terrified that among the injured is Ben, Bailey rushes out to meet the ambulances. One arrives without its siren on, leading Bailey to say, "there's a dead person in there."

Eric McCandless/ABC via Getty Images

Thankfully Ben is okay — but one of the show's original firefighters, Miller, is not, and they have to break it to Vic that he didn't survive. The heartbreaking news leaves her unconscious. While the doctors are able to bring her back, and she doesn't need surgery, firefighter Travis Montgomery (Jay Hayden) explains why her recovery will be extra difficult.

She and Miller were "a different kind of close," he says. "And I hate knowing what she's about to go through, because she's already had to do it once. I can't imagine having to do it again."

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Ben is also forced to tell Bailey that he had agreed to take in Miller's daughter if anything happened to him, and Bailey is frustrated he didn't say anything to her about that promise sooner. She later admits that while she's always wanted a girl, she's afraid if she agrees, someone will end up taking the baby away and she wouldn't be able to stand that heartbreak.

"You know how badly I always wanted a little girl... but it hasn't been in the cards for me. For us," she tells Ben, sharing her fear that the baby's grandparents will come asking for custody. "I cannot do that."

At the end of the day, Jo Wilson (Camilla Luddington) reminds Bailey just how lucky Miller's daughter is to have her and Ben in her life — just as little Prew is brought to the hospital to be with them. The episode ends with Bailey seemingly convinced.

Meanwhile, in Minnesota, viewers are reintroduced to E.R. Fightmaster as Dr. Kai Bartley, who is a member of Dr. Meredith Grey (Ellen Pompeo) and Amelia Shepherd (Caterina Scorsone)'s research team along with Peter Gallagher's Dr. David Hamilton and — surprise! — Tom Koracick (Greg Germann).

Hamilton is very upset when Koracick shows up, later revealing to Meredith it's because the neurosurgeon once slept with his daughter.

"It's not the sex for the record, it's the gloating," Hamilton tells Meredith. "It's my lab, my research, my money. His name is not going to be anywhere near this."

Later confronting him, Meredith reminds Hamilton that when he hired her to lead their research, he gave her complete autonomy in picking the team. Hamilton tells her that he's really upset because his Parkinson's disease is making him lose his "purpose."

To ease his concerns about Koracick, Meredith jokes that maybe Hamilton will end up being able to fire the neurosurgeon. "Wouldn't that be fun?" she says.

Grey's Anatomy airs Thursdays at 9 p.m. ET/PT on ABC.