Gru’s family just got bigger, thanks to the discovery that he has a twin brother named Dru. Set to Dr. Dre, Eminem and X-Zibit's ' Whats the Difference ,' Gru (Steve Carell) is tempted to return to his old villainous ways and do one last heist with his long-haired, super rich twin, Dru (also voiced by Carell).