The top-ranked female assassin known as 'Snow Fox' perished during a high-stakes mission and underwent a mysterious soul transformation into the body of Cassandra, awakening in a vulnerable new life. Her manipulative mother orchestrated an encounter with Brandon, the head of the most prominent family in Rilas, leading to a fateful one-night stand. Five years later, Cassandra returns from abroad with her brilliant son, Bryson. When Bryson is taken by Brandon, Cassandra has no choice but to assume a secret identity as Brandon's personal bodyguard to stay close to her child. Through their daily life-and-death interactions, the assassin and the tycoon fall deeply in love. A story of a secret identity and a perfect family reunion.