Xiao Yi --- Ma Si Chao
Xiao Yi is the deputy team leader of the Criminal Investigation Team. He has a unique way of thinking and possesses keen insight, but he struggles with handling interpersonal relationships. Shortly after graduating from the police academy, he solves the shocking "Four-Two-One" case, which earns him the enmity of the leader's disciples. During the process of apprehending the disciples, he tragically loses his lifelong love. Upon returning to the Xia City Criminal Investigation Team, he works with his teammates to solve numerous cases. While unraveling these mysteries, Xiao Yi gradually discovers hidden secrets surrounding the "Four-Two-One" case. Through the process of solving the case, he finally confronts and overcomes the deep-seated issues that have plagued him for years.
Bai Zhe --- Liu Yi Tong
Bai Zhe is characterized by meticulous thinking, adeptness at manipulation, and skillful disguise. His goal is to clear the name of his father, Bai Shuguo, who died tragically while wrongfully accused. Bai Zhe constantly shifts his identity, navigating between the realms of righteousness and evil. During his investigation into the truth, Bai Zhe is influenced by Xiao Yi, and he gradually develops the intention to bring the evildoers to justice. In the end, he employs his own methods to ensure that the murderers face the consequences for their actions.
Liang Dong Ni --- Jiang Zhuo Jun
Liang Dongni is a member of the Serious Crimes Unit in the Criminal Investigation Team. She is kind-hearted, sensitive, and possesses a strong sense of empathy. Liang Dongni excels at gathering and organizing the necessary information for investigations, making her a crucial support in solving cases within the police force. Through her collaboration in resolving one perplexing case after another, Liang Dongni undergoes a significant transformation. From initially being a somewhat confused and inexperienced young officer, she gradually grows into a resilient and outstanding police officer, displaying strength and determination in her work.
Dou Zi Lin --- Gao Ge
Dou Zi Lin is a member of the Serious Crimes Unit in the Criminal Investigation Team, and he is commonly known as "Douzi." He has a deep-seated hatred for evil and possesses exceptional physical abilities, making him the team's powerhouse in terms of combat skills. Although he may appear unconventional, his inner nature is pure and passionate. As Xiao Yi's junior, Dou Zi Lin has always aimed to surpass him, and their cooperation is seamless. Privately, Dou Zi Lin cares about Yao Shu Bei's opinion of him and strives to impress her. He often showcases his abilities in front of her, hoping to gain her attention and admiration.
Xing Man --- Ge Xin Yi
Xing Man is the daughter of a murderer. She is rebellious and stubborn, and once she sets her mind on something, nothing can sway her. Growing up without the care of a family, she spiraled into self-destructive behavior due to her father's sensitive identity. However, she is later adopted by Xiao Yi's master, Tian Fengling. Despite knowing that Bai Zhe is engaging in illegal activities for the sake of revenge, Xing Man not only deceives her adoptive brother, Xiao Yi, but also falls in love with Bai Zhe without hesitation.
Yao Shu Bei --- Zheng Ying Chen
Yao Shu Bei is a forensic expert in the Serious Crimes Unit of the Criminal Investigation Team. She approaches her work with rationality and objectivity while harboring intense and profound emotions. When her close friend is killed by disciples, she blames Xiao Yi for the tragedy. Upon Xiao Yi's return to the Xia City Criminal Investigation Team, she privately holds biases against him. However, through their collaboration in solving a series of perplexing cases, Yao Shu Bei eventually reconciles with Xiao Yi. They put their differences aside and work together to achieve their common goals.
