Born KO TAI-HEI, Detective COLUMBO has an IQ of up to 283, and is able to achieve a detection rate as high as 99%. Despite his outstanding credentials, he is labeled as a dangerous and combative figure that needs to be kept under watch. COLUMBO has launched a massive dragnet for three suspected kidnappers of a comprador. Having learnt from his subordinate PAU PING-ON that the crime scene has been brought under control, COLUMBO starts eating and drinking inside a tent. ROBINSON is taken hostage by one of the kidnappers and later gets shot by COLUMBO in the confusion. Fuelled with anger, ON blames COLUMBO for being too unscrupulous with everything he does. During their conversation, ON keeps addressing COLUMBO as “HEI”. Superintendent SCOTT is COLUMBO’s supervisor and has long been a thorn in his flesh……

Flashbacks: LOUIS reveals to HEI how he got to know his father KO NGAU. Now that NGAU has passed away, LOUIS needs ON to help arrange a final meeting for HEI and his late father. With the help of LOUIS, HEI has not only acquired permanent residence in Hong Kong but is also sent to the Police Academy for a series of training sessions. Unfortunately HEI has failed in all subjects and the then Academy Principal SCOTT is going to kick him out of the school soonish. Knowing that HEI will be expelled from the Police Academy for his poor performance, ON notifies LOUIS at once and LOUIS is kind enough to intercede for HEI. ON’s wife and mother are caught in a fire, but they just get rescued by HEI in the nick of time. ON has regarded HEI as a member of his family ever since then……

A senior officer orders LUNG to engage in a fencing duel with EVA, and LUNG manages to defeat the girl in just a few seconds. EVA comes to see LUNG as his supervisor and asks him to follow her instructions in all circumstances. EVA would like to see COLUMBO, but ON comes up instead explaining that COLUMBO is busy dealing with a tough case, which is also the biggest drug case in Hong Kong’s history. As EVA is almost frightened to death by a swarm of cockroaches inside the warehouse, COLUMBO shows up and comes to her rescue. COLUMBO explains to the journalists that the whole operation is led by EVA, which causes EVA to make quite an impression on him. Though becoming more and more annoyed with COLUMBO, ON believes that this man still has a conscience and he is still looking forward to his reunion with the original HEI……

ON is shocked to see COLUMBO break down crying with the china doll in his hand. The headache-stricken COLUMBO asks for an urgent brain operation in order to transform back into his original self. At his request, ON sends COLUMBO to the hospital at once. Fearing that the surgery might go wrong in one way or another, COLUMBO pleads with ON to write a letter to MUI to let her know that the china doll has already been repaired. LOUIS asks ON to look for COLUMBO, but instead of following the instructions, ON hands him a resignation letter on behalf of the renowned detective. In the meantime, LOUIS gets a long-distance call from the Hong Kong Governor who is currently on duty in London. LUNG visits his mother’s grave on the anniversary of her death, during which he takes a vow never to engage in gambling and bribery as his father CHOI TIN did in the past. LUNG is surprised to hear that TIN will be working with him in the same office……

ON is awakened by the baby’s crying in the early morning. With no better alternatives, he decides to bring the baby back to the police station. Manager WONG and his wife are shocked to see their son in the police station. Surprised yet happy, the couple grab back the baby at once. To avoid any possible trouble, ON claims to have found the baby outside the police station. ON finds COLUMBO so annoying that he cannot stand him anymore. COLUMBO shows ON a remittance receipt claiming that he has sent HK$500,000 to his wife in the UK. Not wanting ON to cause him any trouble, COLUMBO urges him to leave Hong Kong as soon as possible. ON takes out the china doll, but to his great surprise, COLUMBO grabs it and throws it onto the floor without a second thought. COLUMBO pretends to be so concerned about EVA’s relationship with LOUIS, as if he is most reluctant to see her argue with her father only for his sake……