A woman named Jieum Ban possesses the extraordinary ability to remember all of her past lives. After living and dying nearly a thousand years across eighteen reincarnations, she has grown weary, carrying the joy and pain of countless memories. In her eighteenth life as a twelve-year-old girl named Juwon Yun, her heart is finally moved by a kind and lovable boy named Seoha Mun, and she promises to stay by his side. However, their time together is abruptly cut short when she dies in a tragic car accident, passing away in Seoha’s arms and leaving him deeply traumatized by the loss.

Jieum is reborn less than a year later into her nineteenth life, now as a girl from a poor and abusive family. Determined to reconnect with Seoha, she uses the accumulated knowledge and skills from her past lives to escape her circumstances, excel academically, and eventually secure a position at the hotel owned by Seoha’s family as a young adult. Her goal is straightforward: to meet Seoha again, now the managing director of the hotel, and pick up where they left off. However, she discovers that the passage of time and the trauma of her death have changed him. Seoha is haunted by the memory of Juwon dying in his arms, leaving him emotionally closed off, cynical, and resistant to romance despite feeling a strange and unnerving familiarity with Jieum.

The story is set primarily in contemporary South Korea, following the characters through the corporate environment of the MI Hotel and the personal spaces of their intertwined lives. As Jieum persistently attempts to break through Seoha’s defenses, she gives him an ultimatum, asking for three chances to be with him, after which she will give up if he rejects her each time. The closer she gets to Seoha, the more entangled she becomes with the people from her previous life, including Chowon Yoon, her older sister from her eighteenth life, which creates complicated situations and threatens to expose her secret.

Key narrative arcs include Jieum’s struggle to reveal her identity as the reincarnation of Juwon, a truth Seoha finds impossible to believe. This leads her to orchestrate a series of events and leave clues that force him to confront the impossible reality of reincarnation. A major turning point occurs when the hidden truth about the tragic accident emerges, revealing that it was not an accident but a murder attempt targeting Seoha, meaning Juwon’s death was a case of mistaken identity. This revelation deepens the central conflict, as Jieum must navigate Seoha’s guilt, her own fear of not being accepted, and the dangerous circumstances surrounding his family while trying to build a new relationship on the foundation of a past life’s love.