Kim Sum (Kang Hae-lim) is a developer for social connecting app "Somebody." Even though she has difficulty communicating with other people, she is friends with Mok-won (Kim Yong-ji) and Gi-eun (Kim Soo-yeon). Her friend Gi-eun works as a detective. A murder takes place and the app "Somebody" is involved in the murder case. Architectural designer Sung Yun-oh (Kim Young-Kwang) appears in front of Sum and her friends. Yun-oh is an attractive man, but he seems to be hiding something. Meanwhile, Gi-eun investigates the murder case with help of Mok-won.
