When dozens of critical patients flood the ER, Robby and his team struggle to keep up amid quickly diminished supplies.

As the night shift begins, Robby refuses to give up on a mass casualty victim. Samira and Santos each attempt risky moves.

While Robby attends to an elderly patient with ties to Pittsburgh's history, other members of the team attempt to resuscitate a young drowning victim.

Robby resorts to unorthodox methods to convince a father to allow treatment for his son. Later, Whitaker tracks down a missing patient.

With the Pitt down a staff member, Robby relies on his team to pick up the slack. Later, Santos finally voices her suspicions.

While Robby struggles with a loss, Abbott coaches Samira through a risky procedure, and Mel treats a teen with a mysterious rash.

After a staff debrief from Robby, Dana defuses a waiting room brawl, Whitaker finds common ground with "The Kraken," and McKay faces a crucial error.

While Robby tries to keep a developing staffing situation under wraps, Collins guides a surrogate through a difficult delivery.

Robby helps siblings navigate their elderly father's end of life care. Later, Samira fends off cops targeting a woman with a misunderstood condition.

Bets are taken on the whereabouts of a stolen ambulance, while Santos learns a hard lesson, and Whitaker helps to tame “The Kraken.”

Samira does her best to keep Whitaker on the right track. A teen overdose sparks conflict in the ER.

Santos and Collins each deal with moral quandaries. Samira’s careful approach earns praise from patients – and reproach from Robby.

After examining an influencer with strange symptoms, Samira pushes back against Robby. Santos contends with a patient accused of assault.

While attempting to distract himself from the anniversary of his mentor's death, Dr. Robby introduces a fresh batch of interns to life in the ER.

While Robby handles an ultimatum from the hospital, Mel, Javadi, and Collins each handle unique mother-daughter dynamics.