A newly appointed, sunshine-bright intern begins working under Dr Mason Tucker, the hospital’s youngest attending and its most feared enforcer of protocol. Where she is warm, impulsive, and instinct-driven, he is controlled, clinical, and relentlessly by the book. From day one, they clash—her optimism against his rigidity, her chaos against his precision. Their professional war plays out in corridors, wards, and high-pressure cases where every mistake matters and neither is willing to back down. But when the hospital is placed under lockdown during a mass-casualty shooting, hierarchy collapses and survival takes over. Forced into close proximity without the structure they rely on, Mason and the intern must work together to keep patients alive as fear, chaos, and impossible decisions take hold—changing the way they see each other, and themselves, forever.