Set in the weeks after Resistance: Fall of Man, Resistance: Retribution follows the story of former British Marine James Grayson. After a personal tragedy he is forced to kill his own brother inside a Chimeran conversion center  Grayson goes on a vendetta to destroy every conversion center he can find. Eventually Grayson learns that his efforts have been futile. in Western Europe the Chimera have evolved a new method of converting humans to aliens. The European resistance the Maquis enlist Grayson's help, and he joins Cartwright and Parker in Operation Overstrike. The war to retake the European continent has begun.