Si-jin and Dae-young engage in a perilous operation in Afghanistan, while Mo-yeon assists in surgery. Later, Si-jin and Mo-yeon take in a movie.

Si-jin and Alpha Team join Mo-yeon and the doctors in Urk. Meanwhile, Myung-ju doesn't like how her father, Lt. Gen. Yoon, treats Dae-young.

Tempers flare over a dying man when Mo-yeon insists she can save the patient's life. Meanwhile, Dae-young and Myung-ju reunite at the airport.

After sharing a moment, Mo-yeon isn't sure what to think about her relationship with Si-jin. Later, Si-jin receives a panicked phone call.

After a powerful earthquake strikes Urk, the country descends into chaos. It's up to the medical team and soldiers to search for survivors.

In the earthquake's aftermath, heartbreaking decisions must be made by Si-jin and Mo-yeon, who both strive to save as many people as possible.

When an aftershock strikes, Mo-yeon sees firsthand just how dangerous Si-jin's job can be. Later, an old phone message is accidentally broadcast.

Mo-yeon is embarrassed after her unintentional confession, but Si-jin isn't about to let her off the hook. Meanwhile, a visitor makes everyone nervous.

Dae-young is rattled after seeing an old nemesis, Mo-yeon shares a dark dinner with Si-jin, and an unusual package arrives from home.