Yeon Ji-wo

Lee Sang-jun (played by Lee Jeong-jae) lost part of his memory due to a car accident. When he looks at a photo with excessive exposure, it touches the deepest part of his memory. It was a girl's face. His subconscious told him that there would be a very important memory related to this girl, so he asked his old classmate, Jiang Yongyi

Former intelligence agency agent Min Ki-heon (played by Gong Yoo), who is on the verge of death, happens to meet Seo Bok (played by Park Bo-gum), the "immortal" who holds the secret to human immortality. Min Ki-heon's last mission is to protect Seo Bok to a safe place at all costs. Along the way, a huge financial group and various evil forces that want to possess the immortal launch a large-scale hunt