Marie Heaton is an accomplished Seattle anesthesiologist who thrives on the precision and challenge of her job, until a nightmarish operating room disaster leaves a child dead and launches a complicated malpractice suit. Marie endures the weight of guilt, legal maneuvering, and the looming possibility of losing her career and her carefully ordered life, but through it all her friend and colleague Joe Hillary becomes her source of support and possibly more. Meanwhile, Marie’s family is also in turmoil. Her father is losing his sight and, without an intervention, a series of accidents could worsen into something more serious. Marie’s sister is preoccupied with caring for her own family, and although Marie has been estranged from her father for years, she can no longer justify keeping herself at a distance. As her life and career fall to pieces, Marie uncovers the fault lines of responsibility, betrayal, and truth that can divide us, and discovers that conviction and love --- like oxygen --- can sustain us.