On the first day of school, Park Sae Roy (Park Seo Joon) gets into a fight with his wealthy classmate Jang Geun Won (Ahn Bo Hyun) who is bullying another student.
Geun Won's father (Yoo Jae Myung), the CEO of Jang Ga Group and head of the restaurant where Sae Roy's father works, demands that Sae Roy apologizes to his son but Sae Roy refuses. This triggers a series of unfortunate and volatile events resulting in Sae Roy's incarceration.
Embittered, Sae Roy plots his revenge in prison against the Jang family and their company, Jang Ga Group. The path of revenge is set into motion upon Sae Roy's release as he opens up his own restaurant in Itaewon. There he meets a social media celebrity, Jo Yi Seo (Kim Da Mi), whose real personality is nothing like the angelic persona she portrays online.
