
After a brain injury erases the last eight years of Dr. Amy Larsen's life, she must navigate an unfamiliar world where she has no recollection of patients she's treated, colleagues she's crossed, the soulmate she divorced, the man she now loves or the tragedy that caused her to push everyone away. She can rely only on her estranged 17-year-old daughter, whom she remembers as a 9-year-old, and a handful of devoted friends, as she struggles to continue practicing medicine, despite having lost nearly a decade of knowledge and experience.

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.

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 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.