L.U.C.A.: The Beginning

Zi O, injured from the fall, is hospitalized in the ICU. Meanwhile, Gu Reum's childhood memory of Zi O at the hospital prompts her to investigate his identity.

Zi O takes Gu Reum to a safe place for her recovery. When she asks about her parents, he can't recall. To help jog his memory, Gu Reum brings him to a church.

Zi O remembers burning down the orphanage, shocking him. Gu Reum joins him for tests at Jong Hwan to uncover his past, leading to more chilling memories.

Gu Reum invites Zi O to her home, seeing he has nowhere else to go. While there, Zi O senses Gu Reum's loneliness and despair as she searches for her parents.

ZiO revisits his childhood lab, meeting someone who reveals a startling truth. Meanwhile, GuReum finds a fresh lead in her search for her parents and continues her investigation.

In the lab chaos, Gu Reum and Zi O reunite. Despite her efforts, Zi O clashes with Lee Son, then rushes Gu Reum to the hospital, guilt-stricken for harming her again.

To protect Gu Reum, Zi O takes her to a ranch he worked at years ago. Spending time there, Zi O discovers the simple joys of ordinary life for the first time.

Captain Choi informs Gu Reum at the captive site, leaving her shocked. Meanwhile, Zi O sets up a meeting with Won Yi at a remote location.

As Won Yi's safety is jeopardized by their connection, Zi O sinks into despair. Desperate to find Gu Reum and their baby, he resorts to increasingly risky measures.

Amid cult adulation, Zi O decides on drastic actions for Gu Reum and their child. Despite her efforts, they remain at odds, disagreements persisting.

Zi O dreams of a new world for Gu Reum and their child, while Gu Reum hopes for his return to humanity. Despite their different paths, can they reunite?