Lawyer Gan Zuzan (Michael Tse) and criminal prosecutor Kuang Tin-lam (Tavia Yeung) were originally a couple living together, but a failed proposal led to their breakup. However, fate plays a trick on him. Zuzan has just changed his job to become a criminal prosecutor and lives with Tin-lam again. However, the two have completely different methods of handling cases. Coupled with the intervention of his new secretary Zhu Shuangyue (Grace Wong), their bad relationship has reached an irreparable point. However, Zuzan has been brooding over the rejection of the marriage proposal, but who knows that Tin-lam really has another secret... On the other hand, his father Gan Gan Bodi (Sammy) and Zuzan, an orphan adopted by Baoxiang (Hui Shaoxiong), are like brothers. As a detective in the serious crime team, Bodi often has the opportunity to cooperate with Zuzan. During an operation, he met undercover agent Amy Chan (Sharon Chan). The two are incompatible but complement each other's strengths and weaknesses. Bodi decides to pursue Meichen, who already has a fiancé, regardless of their background. Just as they are hesitating about the future, a murder case involving female tycoon Pang Tiexin (Alice Chan) makes them go through a difficult and dangerous battle together...