While investigating a serial murder case, Han Tae Joo gets into an incident. When he wakes up, he finds himself back in 1987. To get back to his present world, he must solve the murder case.

An office romantic-comedy features the hijinks that ensues between a tempt worker with possible terminally-ill diagnosis and a prickly elite marketing director.

Born in a poor family, Tae-su learns that the power is the most important thing in life and decides to become a prosecutor, the biggest symbol of power in the 90’s. After entering the most prestigious law school, experiencing democratic resistance in Korea, Tae-su finally reaches his goal of becoming a prosecutor but his life is no better than a salary man. By chance, he joins a clique of the powerful prosecutors with wealth and authority. He finally gets a taste of a life of the top hierarchy, but as he enjoys the sweetness of supremacy, he also sees the cruel side of it.

Woo-Jin changes into a different person when he wakes up. He falls in love with Yi-Soo.