The story of a mysterious taxi service that takes revenge on behalf of victims who are unable to get justice from the law. Kim Do Ki is a mysterious driver for the taxi company whose mother was murdered. Kang Ha Na is a passionate attorney. Go Eun is an IT specialist, while others consider her a hacker. Along with Kim Do Ki, she works as part of Rainbow Taxi Company to solve people’s problems.

Set during the turbulent time of the fall of Goryeo and the founding of Joseon, two former friends face-off against one another over a woman and the future shape of the nation.