Amy treats a rural patient whose condition has worsened significantly due to a lack of medical resources; as Ben prepares to launch the artificial heart surgery trial, Jake grapples with his role in deciding which patient gets to go first.

Revelations about Amy's brain health put her future at Westside in jeopardy; Gina pushes the limits of medicine to revive a patient who seems beyond saving; Ben begins human trials on his artificial heart implant.

Amy and Jake work together to treat a patient whose secret past puts her life in danger; after a key donor withdraws funding, Ben must scramble to save his artificial heart trial; Sonya and TJ's relationship is tested when Sonya's father visits.

Amy must help a family process the news that their daughter's sudden illness could be fatal, while enduring a barrage of intrusive memory seizures; TJ and Sonya are forced to work together to treat a man whose injuries appear to be self-inflicted.

Amy and Ben go toe to toe when their cancer patient demands the impossible; Jake discovers a senior Westside surgeon has botched an operation, and he must decide whether to speak out and risk his tenuous new position in cardiology; Sonya grapples with the weight of life-changing news.

Amy and Jake are paired together on a bizarre case that lays bare the still-raw feelings surrounding their fractured relationship; Michael and Sonya are thrust into a family crisis while trying to save a young addict.

When a horrific accident sends three members of the same family to Westside in critical condition, the entire staff must band together to save them and avert tragedy; Amy must contend with a flood of emotional memories as she goes head-to-head with mysterious newcomer Dr. Ben Grant.

On Amy and Sonya's first day as co-chief resident, they must coach a fresh crop of interns through a mysterious case that seems to defy medical logic; Jake and TJ adjust to new roles within the hospital; Dr. Ben Grant returns to Westside.