Against the backdrop of a long string of burglaries in Chicago, the meek family man and conscientious surgeon, Dr Paul Kersey, is juggling career and family to support his wife, Lucy, and his college freshman daughter, Jordan. Then, his life turns upside down when three brutal masked robbers break into his house, and Kersey's family becomes a statistic. As a result, with the authorities unable to apprehend the perpetrators, Paul is starting to lose faith in the ineffectual system, and before long, he plucks up the courage to become a vigilante, and take the law into his own hands with his semi-automatic, 4th generation Glock 17 pistol. Now, Paul thinks it is high time he gave them a dose of their own medicine. But, isn't a doctor supposed to save lives?