A serial killer who calls himself &quot;The Executioner&quot; appears in Cishan City, disrupting the police.<br /> Detective Captain Lim Yoo is forced to become the deputy head of the task force and work with the new team members to solve the cases.<br /> At the beginning of the case layer by layer to unravel the curtain, but also opened a thirteen years after the old case.<br /> In the past thirteen years, Lin Yu was disturbed by his own confused memories. Traveling through thirteen years, Lin Yu reunites with his former &quot;old acquaintances&quot;.<br /> This time, Lin Yu and his former &quot;old acquaintance&quot; reunite, and this time, they join forces again, not knowing whether they will be brave enough to win, or work hand in hand to solve the strange case. ......<br /> The accident hidden thirteen years ago becomes a life-and-death battle between Lin Yu and his friends.