A boy named Neku Sakuraba finds himself in the middle of what appears to be Shibuya, discovering that he is on a plane known as the Underground, separate from the Realground regular people are on. Upon receiving a mission on his phone telling him to reach the 104 Building or else face erasure, monsters known as Noise attack Neku. A girl named Shiki Misaki saves him, and they form a pact, granting him the ability to use "Psychs" to defeat the Noise...