Professional mercenary Karl Thomasson arrives in Brooklyn to attend the funeral of his brother Randall, who was murdered while trying to stop a carjacking that has been blamed on the "Brotherhood", a vicious street gang led by "Little B." Karl, who believes there is something more to it, goes undercover as Randall's replacement at Lenthrop High School in Brooklyn, where Randall was a history teacher, so Karl can investigate the Brotherhood. Karl becomes the protector of Randall's daughter Anya...