A hacker compromises the hospital’s computer system, causing monitors, phones, labs and patient files to all go down. As technology fails them, Bailey attempts to keep the peace but chaos erupts and the doctors are forced to get creative in their methods to treat the patients.

A young boy is admitted to Grey Sloan Memorial and his case has a profound impact on the doctors. Meanwhile, April is faced with a surprising patient, and Jo continues to deal with her estranged husband.

Maggie and Jackson are enjoying spending time together, but he must turn his concentration toward the groundbreaking vaginoplasty surgery he has scheduled with Catherine and Richard. Meanwhile, Meredith and Jo hit a roadblock with their contest submission, so Jo helps Bailey with an incoming trauma patient who used to be an astronaut

Meredith works on a patient who happens to specialize in matchmaking, and a seemingly drunk patient pushes Richard's buttons and gives him a medical mystery to solve. Meanwhile, Maggie tries to reach Teddy after bearing the burden of her secret becomes overwhelming as she struggles with issues in her own personal life.

Catherine is in Los Angeles getting the new foundation ready and summons Meredith and Koracick to visit for a highly confidential consult. Meanwhile, one of the nurses is 28 weeks pregnant and collapses at the hospital while talking to Richard.

Amelia and Koracick tackle a daunting surgery on Catherine while Richard and Jackson hope for the best. Meanwhile, Richard urges Meredith to visit her father, Thatcher, before his time is up.

When a trauma patient arrives at Grey Sloan, it forces Jo to confront her past. Meanwhile, Bailey and Ben have to talk to Tuck about dating.

Catherine is back in town and has no idea what’s been going on between Jackson and Maggie, while her relationship with Richard has become distant. Owen and Amelia treat a woman who fell in the basement and quickly realize that there is more to the story, and Maggie is shocked to learn about some of Richard’s relatives who are seeking help.

Richard finds out Maggie quit Grey Sloan and is concerned about how she’s handling the death of her patient who was her estranged cousin. Bailey returns to work after taking some personal time off, although Koracick doesn’t make her first day as easy as she’d like. Meanwhile, Meredith thinks she might miss DeLuca, and Amelia has an update for Link on her pregnancy.

DeLuca is irritated after Meredith takes over his patient Suzanne whose symptoms continue to stump the doctors at Grey Sloan. Elsewhere in the hospital, Jackson, Owen and Jo work on a couple injured in a bear attack; and Levi is hurt when Nico doesn’t want him to meet his parents.

Link tries to convince Amelia to take it easy during the final stage of her pregnancy. Hayes asks Meredith a surprising question, and Owen makes a shocking discovery.

The doctors of Grey Sloan Memorial must contend with the COVID-19 pandemic; an unintentionally started fire has first responders from Station 19 bringing patients into the hospital for treatment.

The Grey Sloan doctors continue to face their new COVID-19 reality and deal with a familiar and stubborn patient. Koracick is put in charge of the interns who recently joined the hospital ranks and Link operates on a sex therapist. Elsewhere, Maggie finds comfort in Winston's virtual presence.

Grey Sloan Memorial faces new pressures as Seattle Pres is overloaded, and Grey Sloan Memorial is now on surge capacity protocol. Meanwhile, Owen and Amelia are faced with one of the most controversial surgeries of their careers.

Meredith seeks advice from Amelia. Meanwhile, Richard is reenergized as he takes teaching to a new level at the hospital, and Winston treats a patient suffering from kidney failure.

The Grey Sloan doctors spring into action after an explosion rocks Seattle, with the incoming trauma hitting close to home. Owen experiences PTSD after he hears the explosion, while his sister Megan enlists help from Winston and Hayes in confidence. In Minnesota, Meredith and Amelia meet up with a familiar face who assists in their study.

The crossover starts on Station 19 S05E05 Things We Lost in the Fire (I).

Tensions at Grey Sloan Memorial rise as the effects of the physician shortage begin to show. Meanwhile, Meredith struggles to step away from work as she spends a sick day at home with Zola, and the hospital receives an unexpected visitor.

Due to a blood shortage, Grey Sloan Memorial is setting up a voluntary donation center. Meanwhile, Nick asks Meredith for help with his patient and Winston is hung up on his relationship with his brother.

Bailey recruits the interns to create a series of social media videos informing teens about sexual health. The videos, filmed at Grey Sloan in front of a group of high schoolers, hit home as a student has medical complications during her visit. Elsewhere, Meredith and Maggie learn something new about Zola.

The attending surgeons fly to Boston, forcing a reunion between Nick and Meredith. Bailey gets a big surprise.

It's all hands on deck at Grey Sloan when a group of medical students is injured by a floor collapsing at their white coat party. Jo and Link are forced to talk about the future, while Jules confronts Winston about his attitude.