Dr. Samantha Ruiz, a former combat medic, has left her life in the military behind to take up a position at a hospital in Boston. But when the Irish mafia takes over the hospital in a bid to free one of their own from police custody, she finds herself at the center of a deadly standoff.
Samantha's son, Tyler, had come to visit her at work that day, and when he becomes caught up in the chaos, the stakes become even higher. With her son's life on the line, Samantha must use all the skills she learned in her time as a medic to stay alive and keep Tyler safe.
As the situation inside the hospital escalates, Samantha finds allies in some of the staff, including a nurse and a security guard, but they are quickly picked off by the ruthless mobsters. Samantha is forced to confront her own past and come to terms with how it has shaped her into a deadly weapon.
The tension builds as Samantha and Tyler move through the maze-like hospital, pursued by the mafia and forced to improvise weapons and tactics to stay ahead of them. At every turn, they encounter new dangers, from rigged explosives to snipers positioned outside the building.
In the end, Samantha must face off against the mafia boss in a final showdown, using her strength and cunning to take him down and save Tyler. But as the dust settles and the police take control of the scene, Samantha knows that the trauma of this day will stay with her for a long time to come.