365: Repeat the Year — Characters & Cast

Initially driven by the selfish desire to undo a personal tragedy, his motivation broadens into solving the serial murders, protecting Ga-hyun, and stopping a calculating monster.

Starting as a traumatized homicide detective paralyzed by survivor guilt over his partner’s death, Hyung-joo jumps at the reset solely to resurrect his fallen mentor. Over the series, he evolves from a reactive, guilt-driven cop into an observant, selfless protector who is willing to shoulder the psychological burden of an entire forgotten timeline alone to ensure justice and safety for others.

Evolving from personal physical autonomy to uncovering the truth behind the reset and preventing the deaths of innocent people.

Initially portrayed as an irritable, workaholic webtoon writer embittered by the loss of her legs and betrayed by loved ones, she enters the reset solely to regain her physical mobility. As she confronts the unraveling death game, she sheds her misanthropy, becoming a courageous investigator willing to place her life on the line to save Hyung-joo.

Repeating time endlessly to find a single temporal pathway where her terminally ill young daughter survives.

Presented as an all-knowing, almost supernatural architect of fate, she is gradually revealed as an ordinary, desperate mother trapped in an agonizing loop. Confronted by the collateral damage of her repeated experiments and the limits of medical destiny, her facade cracks, forcing her to accept loss and release her control over the timeline.

The thrill of murder, evading detection, and preserving his facade of honor.

Viewed by Hyung-joo and the precinct as the quintessential supportive senior officer, his character is unmasked as an active serial predator whose survival in the reset timeline allows him to kill repeatedly while exploiting his police badge to bury evidence.

Securing funds for his sister's welfare and navigating the dangerous underworld created by the resetters' secrets.

Initially framed as a sinister, corrupt ex-convict who seemingly stalks and extorts the resetters, he turns out to be a pawn gathering information for financial survival while desperately trying to shield his sister. His eventual cooperation with Hyung-joo humanizes him before he falls victim to the real killer.