Lee Ho Cheol is just an ordinary guy who works as a firefighter. One day, when news about a serial killer was making headlines, Lee Ho Cheol receives a piece of information from a stranger informing him that the serial killer is his neighbour, Kwon Shi Woo. Unknown to Lee Ho Cheol, the stranger who gave him that information is a contract/hired killer, Bae Tae Jin, and Lee Ho Cheol suddenly finds himself trapped in a situation between the two. Adapted from the novel "Superior Day" (우월한 하루) by Team Getname (팀 겟네임).