Season synopsis
Contains spoilers for this season and earlier seasons.
County General enters a difficult year as Mark Greene’s health begins to fail again and Susan Lewis returns to the ER. Greene and Corday’s family is strained when their young daughter Ella swallows ecstasy pills from Rachel’s backpack and nearly dies. Corday blames Rachel and wants her sent away, while Greene resists turning his troubled teenage daughter out of the house. Their disagreement deepens as Greene learns his brain tumor has returned, is inoperable and gives him only months to live. He undergoes a gamma-knife procedure and initially keeps the news from Corday.
Greene’s illness changes his work and family life. His relationship with Rachel remains painful, but the two begin to address the damage between them. When Rachel calls Corday to Hawaii because Greene is worsening, Corday and Ella join them at his childhood home. Greene spends his final days reconnecting with Rachel and bringing his family together; he dies there from the brain tumor. Carter reads Greene’s farewell letter to the staff, followed by Corday’s note announcing his death. The hospital mourns him at a funeral, and Carter recognizes that he must take on more responsibility in the ER.
Other changes reshape the department around that loss. Carter becomes chief resident after Weaver changes her mind. Abby helps a neighbor escape an abusive partner and faces consequences when the man is released; Kovač intervenes violently against him. Benton leaves County after a custody fight over Reese, while Weaver acknowledges her relationship with Sandy Lopez at work. New residents Greg Pratt and Michael Gallant arrive. In the finale, two children arrive with symptoms resembling smallpox, and Carter orders the ER locked down. The possible contagion leaves staff and patients trapped together in the heat.