Alexander Guy Cook, known professionally as A. G. Cook, is an English record producer. He first became known as founder of the influential record label PC Music in 2013; its signees included Hannah Diamond, GFOTY, Danny L Harle and Felicita. The label's style of exaggerated pop tropes grew to serve as the foundation of the hyperpop genre, which Cook is credited for developing and popularising. He later became more widely known as executive producer for Charli XCX. He has released solo music under both his name and aliases like DJ Lifeline and DJ Warlord.