學警陳志超雖成績名列前茅, 但因得罪探長劉福而被調守梅窩, 卻因一次緝獲當地黑社會頭子而獲派擔任便衣, 更與江湖大家姐義結金蘭. 福無法擺平英軍強姦村女一案, 聽姪兒劉和奸計欲陷害志超, 幸志超化險為夷, 同時亦使劉福威名大增, 此後官運亨通, 引來同僚林光及雷洛妒忌. 志超生性風流, 除有妻何玉珠及妾白素芬外, 更有女友姚卿, 引起素芬不滿, 在自殺及偷漢後, 終弄致分手. 志超因懂得奉承劉福, 遂成為劉福退休後的繼任人, 誓言除暴安良. 時劉和把小歌女郭秋菊賣身給夏爵士, 之後更逼死她, 志超便抓來劉和替秋菊報仇, 更不惜與劉和的老闆雷洛再結樑子. 最後劉福在臨終前來求情, 志超才饒劉和一命. 志超在五十年代多次社會暴亂中均有突出的表現, 故最後獲升為新部門"三支旗"的總舵主, 擁有無上警力, 成為警界神話. Although scoring the highest mark in the final examination, cadet Chan Chi-chiu is sent to an outbound island because he has irritated inspector Lau Fook. He quickly gets promoted after he catches the gang leader in a fight. He also wins the friendship of Sister San, a big sister of a gang. Lau Fook is unable to manage a raping case committed by the British army in a village. His nephew, Lau Woo wants to frame Chi-chiu up but the case is resolved by Chi-chiu. Using the chance to make Lau Fook a hero, Chi-chiu wins the trust of Lau Fook. This provokes jealousy of his colleagues Luke Lui and Lam Kwong. Chi-chiu has a wife Ho Yuk-chu and a mistress Pak So-fan. He is also engaged in many affairs and this upsets So-fan. She tries to commit suicide and involves in extramarital affair to win back her man. When she fails, she sadly separates from Chi-chiu. Since Chi-chiu knows the techniques to flatter Lau Fook, he is appointed the successor of Lau Fook's position. Chi-chiu swears that he will try his best to help the poor and fight against the evils. Therefore when he knows that Lau Woo sells a young singer Kwok Chou-kuk to Sir Ha for money and forces her to death, he arrests Lau Woo to revenge for Chou-kuk. This further irritates Lau Woo's boss, Luke. Before Lau Fook dies, he begs Chi-chiu to leave his nephew alone. In the fifties, Chi-chiu has done a good job in settling many riots and is appointed the head of a new department, nicknamed "Three Flags". This means he is now the man who has absolute police power in hand.