Dr. Jacey Flanigan has worked tirelessly to achieve her dream of becoming a pediatric cardiologist. But when she moves to Manhattan to begin her career at a prestigious children's hospital, she discovers that the medical profession may not be what she expected. An encounter with an arrogant heart surgeon on her first day sets the tone for what's to come - a world of enigmatic physician behavior and questionable cardiac surgical practices cloaked in secrecy.

When her elderly patients start dying at home days after minor surgery, anesthesiologist Dr. Kate Downey wants to know why. The surgeon, not so much. “Old people die, that’s what they do,” is his response. When Kate presses, surgeon Charles Ricken places the blame squarely on her shoulders. Kate is currently on probation, and the chief of staff sides with the surgeon, leaving Kate to prove her innocence and save her own career. With her husband in a prolonged coma, it’s all she has left.

Dr. Mallory Hayes, a Centers for Disease Control and Prevention (CDC) medical investigator, is a committed physician and researcher quietly battling height and air-flight anxiety. When a tsunami devastates the coast of Southern California, the Federal Emergency Management Agency (FEMA) establishes a camp to house the tens of thousands of people displaced by the disaster, and the Army is brought in to provide medical services.

Running away from a past she’d rather forget, Doctor Alison Wilson has moved to a new town to take up the role of Medical Officer at failing hospital St Margaret’s. Tasked with shaking things up, she quickly learns that things are worse than they initially seem: patient records are in disarray, staff morale is low, and there’s something afoot that she can’t quite put her finger on As Alison starts to dig into the hospital’s past, she gradually discovers a trail of lies that runs deeper and darker than she could have ever imagined.

Dr. Jack Wyatt is renowned for solving the unsolvable. When a colleague approaches him about a dangerous new malady affecting only Leukemia patients at a prestigious oncology hospital, the mysterious case is too intriguing to pass up. So he and the brilliant Dr. Madison Shaw, a physician who shares not only his expertise but also his devotion to medicine, embark in a race against time to save the children as cases mount. Within the hospital walls, they confront a labyrinth of medical conundrums, hostile colleagues guarding their territory, and a web of political intrigue.