When E'Dawn from the Kpop group Pentagon and the solo artist Hyuna mysteriously disappear, a young intern working as a coffee assistant at a spy agency is promoted to go on a mission to uncover the disappearance of the two idols. How? She is falsely debuted as an idol to work undercover and hopefully discover the secrets behind the performers. However, will her mask seep deeply into her real identity? Will her mission be completed or will someone uncover her mask? Does she have an intention of her own?