After dying unexpectedly, Su-hong becomes the third soul to be guided through the afterlife by three grim reapers: Gang-rim, Haewonmak, and Lee Deok-choon. The trio must help Su-hong navigate seven trials within 49 days to determine his fate in the afterlife. They function under the watchful eyes of the gods, aiming to achieve reincarnation for Su-hong while contending with their own challenging pasts. As they meet various judges who test Su-hong's earthly misdeeds, the trials prove increasingly difficult, uncovering truths about justice, forgiveness, and morality.

Simultaneously, Gang-rim, the leader of the reapers, ventures into the living world to uncover Su-hong's unresolved family issues, revealing conflict within Su-hong’s family that influences his trials. Parallel to this, Haewonmak and Deok-choon are sent on a mission by the god of House Guardians to retrieve a forgotten memory from their own past lives, which could affect their qualification as guides. These intertwined journeys uncover hidden connections and test their loyalty and morality, compelling each soul and reaper to confront deep-seated guilt and seek redemption.