Ju Yeong is a woman who longs for her ex-boyfriend but doesn't want to accept it. As she ends a short-term relationship with a very obsessive co-worker, her ex-boyfriend suddenly shows up as a new hire that she has to train. However, as rumors spread about her troubled relationship with the two co-workers, she finally realizes it was all her shortcomings that made it this way.

Having died unexpectedly, firefighter Ja-hong is taken to the afterlife by 3 afterlife guardians. Only when he passes 7 trials over 49 days and proves he was innocent in human life, he’s able to reincarnate, and his 3 afterlife guardians are by his side to defend him in trial.

As the deceased soul Ja-hong and his three afterlife guardians prepare for their remaining trials for reincarnation, the guardians soon come face to face with the truth of their tragic time on Earth 1,000 years earlier.

Jae-ho, who aims to become the number one in a crime organization, gets to build up trust with Hyun-su, an ambitious newbie in the prison. While they try to take over the organization after the prison release, their ulterior motives starts to emerge.