Detective Ma Seok-do changes his affiliation from the Geumcheon Police Station to the Metropolitan Investigation Team, in order to eradicate Japanese gangsters who enter Korea to commit heinous crimes.
Kang Woo-ram is busy preparing to get a job. Lee Hyun-ji is a would-be anchor, but she works at a homemade hamburger restaurant. One night, Woo-ram visits the hamburger restaurant and orders a double patty hamburger, which has a "buy one, get one free" sale. This is how their relationship begins.
