Shy Ji-hae's friend is having problems expressing her feelings to the boy she loves, so she asks Ji-hae to write e-mails to him in her name. As the boy falls in love with her letters, Ji-hae discovers the story of her mother's romance which is remarkably similar to her own circumstances.

Jang Young-Sil (Gang Ye-Won) barely lands a job at the NSA (National Security Agency). She is hired as a contract worker to write positive comments for the NSA. Na Jung-An (Han Chae-Ah) is a detective who often uses foul language. They carry out an infiltration operation to recover money that was stolen from her boss in a voice phishing scheme.