The villain actors who play the roles that attempt fraud, murder, and violence are gathered. These Korea's best villain actors who present perfect acting form a team of a cappella called Do Re Mi Fa and sing in harmony. They are full of passion, however, they sound out of tune. Among the members who are diagnosed as unable to hit high notes, their efforts and talents are revealed, from members who have unexpected charms and overwhelm the audience with a natural voice, and members who show off their best lowest vocal range. With Jung Hyung Don and Defconn as the managers of the team, they will assist the seven newbies to variety shows and give them energy. What will their harmony be like?