Sunset Overdrive has been set in the fictional American metropolis Sunset City. The story starts when a resident mega-corporation, Fizzco, hosts a massive release party for its hot new energy drink named Overcharge Delirium XT. However the beverage had been rushed to market. Profit first! Most of Sunset City is transformed into various mutants, also called the “OD’d”. The city is then quarantined and morphs into a chaotic, mutant-infested wasteland.