Former Marine Gunnery Sergeant Ali Gorski returns home to New York after a failed attempt to save the American Ambassador’s eight year old daughter amidst a terrorist firefight in Romania. Hoping to get as far away from the violence of war as possible, she takes a job as a doorman at the labyrinthine old apartment building her brother-in-law Jon lives in with her niece Lily and her nephew Max. When a group of mercenaries led by the elegant Victor Dubois invades the building, intent upon retrieving priceless art hidden in its walls, they have no idea what hell aunt Ali is going to unleash to save her loved ones.