Minsik tries to use Sangchun to cut off Ije's hand, but Ije persuades Sangchun, saying that he will help Sangchun meet his daughter. Meanwhile, Sogeum finds out that Ije injected a drug into Bit before he disappeared.
Ije tells Sogeum of his plans to gain power through the VIPs in the prison's Special Sector. Sogeum, however, is unimpressed with Ije's intentions. Minsik and Ije each attempt to get the list of investors before the other does.
Minsik accuses Sangchun of helping Ije plan Jaehwan's car accident and gives him an overdose of insulin. Ije saves Sangchun after arriving at the prison. Meanwhile, Ije continues to put pressure on Minsik to give up his position as the prison's chief medical officer.
Sun-ho is the serial killer who has been collecting the belongings of the dead resetters. Hyung-joo falls straight into a trap set by Sun-ho.
After Jung-tae's death, Hyung-joo starts acting suspiciously. Meanwhile, Ga-hyun discovers a shocking link connecting all the deaths.
After Se-rin's death, Jung-tae becomes the prime suspect. Meanwhile, Hyung-joo begins to doubt Young-woong's true intentions.
Lee Shin's ominous words foretelling death shock the resetters. Amid the confusion over who will be next, a new truth begins to emerge.
Hye-in's death takes Hyung-joo and Ga-hyun's investigation into a new phase. Meanwhile, Lee Shin's hidden past slowly comes to light.
Hyung-joo and Ga-hyun track down who sent the mysterious flower basket and why. Along the way, they stumble upon an unexpected clue that shocks them.
The tangled relationships among the resetters begin to unravel, and Ga-hyun and Hyung-joo join forces to uncover the truth behind the series of deaths.
Gi Joon starts gathering all available information on Do Hyun. Ri Jin and Ri On calmly handle the sudden appearance of all of Do Hyun's personalities. Meanwhile, Do Hyun receives full authority from Tae Im to prepare for the shareholders' meeting, prompting Gi Joon to meet Young Pyo to strike a new deal.
Do Hyun and Ri Jin recall the shocking truth about their past and fall into panic. Tae Im becomes busy trying to suppress an article about Jun Pyo, while Hwa Ran smiles in satisfaction. Meanwhile, Do Hyun learns from Tae Im the full story behind the fire at the Seung Jin mansion 21 years ago.
Do Hyun takes Ri Jin on a farewell trip aboard the Snow Flower Train. Shin Hwa Ran plots to ensure Do Hyun stays with Seung Jin Group, while Chairwoman Seo Tae Im meets privately with Ri Jin.
Do Hyun begins to recall his lost memories, while Ri On decides to investigate who was behind Ri Jin's childhood abduction. Ri Jin tries to recall her own past for Do Hyun's sake, but he worries for her. Hwa Ran panics when Do Hyun declares he'll make her illness public.
Do Hyun regains his laughter while spending time with Ri Jin's family. Soon Young encourages him to pursue Ri Jin and shows him photos of Ri Jin and Ri On as children. Meanwhile, Do Hyun's repressed memories of the basement resurface, and he meets the personality “Nana.” Chae Yeon calls off her engagement with Gi Joon.
Ri Jin begins having nightmares, worrying Do Hyun. However, she keeps her distance, prompting Do Hyun to reconsider her relationship with Ri On. Meanwhile, Young Pyo becomes convinced that Min Seo Yeon's child is still alive, and Ri On has his first encounter with Yo Na, one of Do Hyun's personalities.
Ri Jin encounters all of Do Hyun's personalities in one night — except for Shin Se Gi. Gi Joon and Chae Yeon are stunned when Ri Jin shows up at the company as Do Hyun's secretary, while Ri On meets Do Hyun under his secret identity as Writer Omega.
Gi Joon proposes to Chae Yeon, but she gets angry at his attitude. Ri Jin agrees to be Do Hyun's secret doctor, but is shocked to learn she has to live in the same house as him. Thus begins their uneasy and awkward cohabitation.
Tae Im questions Director Ahn about the reason for Do Hyun's return to Korea, leaving him flustered. Ri Jin struggles to stop Yo Seob from taking his own life. Hwa Ran orders someone to find Min Seo Yeon's long-lost child, while Do Hyun begins strategizing to meet the mysterious writer Omega.
Do Hyun can't stop thinking about Ri Jin, which only fuels Se Gi's jealousy. Eventually, Se Gi warns him, “If you touch my woman, yours will be in danger.” Provoked, Do Hyun goes to Ri Jin and asks her to become his secret personal doctor.