Uncles Luk runs into heavy debts and wants to sell his daughter to a brothel. Driven by his sense of justice, Yung Yuet San offers help and save Hau Yee, Luk's daughter from becoming a prostitute. San even gets a job for her in Ngai Pang's house. Ip Yuen Sham is impressed by his act. Ngai Pang is the ring-leader of an underworld gang. Both San and Kong Chun Shing are working for him. Shing is once ridiculed by Lui Lung who is the enemy of Pang and he feels very angry. Shing is already engaged to Fong Wing Chuen, the niece of Sister Lau who worries about his unrestrained character. She keeps asking him to reform but he pay no heed to her words. Uncle Cheung's son is seriously sick and he has difficulty in paying the medical charges. Owing to Fang's help, Pang promises to lend him the money. However, Shing refuses to give Cheung the money and he even scolds Cheung fiercely.… ...

Fang is killed when the gangsters try to kidnap Pang. It greatly grieves Pang. San and Ko Han try to locate Pang. San is suspicious of Cheung and he follows him. Yet he is discovered and is wounded in the end. Eventually, San and Han find out Pang's whereabouts and successfully save him. Pang kills the murderer of Fang as a revenge. On the other hand, Shing thinks that Pang is kidnapped by Lung. So he sends his followers to raid Lung's dens. This antagonises Lung. Knowing that Shing has done wrong to Lung, Pang is forced to compensate for his loses. To vent his anger, Shing kills Cheung secretly. He tries to hide this from Pang who gradually loses trust in him. San now becomes Pang's right hand man.

Poon Yuet Wah is angry to learn that San is working in the underworld. But San successfully pacifies her with his glib tongue. Pang asks San and Shing their opinion concerning his collaboration with Mo Kin. San and Shing hold different opinions but Pang takes sides with San making Shing very unhappy. Chuen comes to live with Lau in Hong Kong. San goes to meet her at the 4tation. Shing is trying to avoid her since he fears that she is no good-looking at all. Chuen feels very unhappy about that while San leaves a favourable impression upon her. San and Shan are preparing to get married. Chuen offers them a hand. By accident, Shing meets her and is attracted by her. Pang also meets a very beautiful girl, Chou Ying and starts to court her.

Chou Tat Fu happens to find the lost wallet of Shing and gambles away the money. He is later discovered and is beaten. Ying comes in time to save him from the hands of Pang. By mistake, Ying hurts Han but Pang lets them go. Pang starts to date Ying and helps to settle Chou Moons debts. Ying feels indebted to his kindness and promises to marry Pang. After much negotiation, Kin and Pang enter into an agreement for collaboration. Accidentally, Wah finds Kin and San having a business meeting. She is greatly shocked to see Kin.

In fact, Wah recognizes Kin to be the murderer of her parents who at that time wanted to leave the gang. She is the witness and she tells this to San. After investigating, San knows that Kin is really the murderer but he does not dare to kill him because that will bring trouble to Pang. Knowing this, Pang thanks San for -- being so considerate and sends him a flat as his wedding present. Shing overhears their conversation and grows jealous of San. Later, San determines to have his revenge and withdraws from Pang's gang. Being close friends, Han decides to follow San who is greatly impressed. Shing betrays San and inform Kin of San's plan. Kin sends his followers to kill San. However, San escapes from the danger but Shan is shot dead.

Kin finds that his plan falls through. So he and Wing Lun decides to leave Hong Kong. San and Han chase after them and they exchange fire. In the end, Kin is killed but Lun escaped. Shing is afraid that Pang will know that he has betrayed San. Yet he is greatly relieved to learn that Pang is still in the dark. Pang even asks him to find out what really happens. Despite pressure from his gang as well as the police force, Pang strongly refuses to surrender San to the police. Chuen symoathizes with San and is angry with Shing who is aggressive and unscrupulous. Lun flees to Guangzhou and sends people to assassin Pang's followers. Pang decides to go to Guangzhou to negotiate with Lun. His being away makes Ying very unhappy. She feels herself often neglected by Pang. When she goes out for a drive alone, she is attacked but luc kily Han is there to save her.

Han bravely saves Ying running the risk of losing his own life. In the end, he is wounded and Ying is deeply impressed. Han and Ying gradually grow fond of each other. Han suppresses his feeling for Ying and tries to avoid her. Ying cannot help dating Han and in the end, the two have an affair. Han feels - deeply regretted for being disloyal to Pang and does his best to avoid meeting Ying. an Pang and Lun eventually come to agreement and Lun promises to let San go while Pang pays for all his loses. On his return, Pang finds Ying treating him coldly. In fact, Ying misses Han who is caught in the tangle. San is surprised to find Han so depressed and soon discovers the truth.

San is angry to find Han being unfaithful to Pang. Han promises San not to see Ying again. On one occasion, Ying arranges to meet Han in her parents' place but Han does not turn up and he even asks San to escort her home. Ying feels very angry about this and what is more, she is shocked to learn that Pang is trying to help Han find a wife. Hence, she arranges to meet Pang in a hotel and lets Pang know that in advance. Pang is infuriated when he learns of their intimate relationship. Not knowing what to do, Han listens to San's advice and tries to flee. Yet they are caught by Shing's men. Han feels very guilty of his wrongdoing and wants to kill himself to atone for his crime. Pang stops him and lets him go but locks Ying up.

Han leaves the gang and works as a labourer at the pier. San often helps him financially and gives much encouragement to him. Their friendship tie grows stronger. Pang's health gets weaker and upon examination, he finds himself having a terminal illness. Knowing that his days are numbered he sets Ying free and she goes happily to .join with Han. Pang entrusts all his business to Shing who is greatly delighted. He also asks San to give a hand to Shing. Chuen feels bored staying all day at home and asks San to find her a tutor. This draws them, closer to each other and they grow fond of one another day by day. Knowing that, Shing treats San badly but San remains tolerant. On the other hand, Chuen finds it harder and harder to get along with Shing. Their engagement finally breaks when Shing sends his followers to beat Chuen's tutor and this makes Chuen feels furious.

Realizing that his days are numbered, Pang is particularly kind to his family. San grows suspicious of his behaviour and is later grieved to learn the truth from Pang. Pang encourages San to court Chuen and even arranges San to escort .Chuen to pay homage to her ancestors. This gives them a chance to get closer to each other. However, this makes Shing indignant. Shing quarrels with another ring-leader Tse Sing. San tries to calm them down but Shing kills Sing.

Shing is blamed by the other underworld ring-leaders. Pang is involved and his health is greatly affected by this. Shing seeks help from San and promises to let him have Chuen if he offers him his help. Both San and Chuen finds him really contemptible. In the end, San still offers Shing his assistance. He tries _ to convince the other ring-leaders that Shing kills Sing out of self-protection. The leaders believe San and let Shing off. Pang feels disappointed with Shing and entrusts his business to San. This makes Shing infuriated. Wah and Chi get married while San and Chuen also .join in marriage. Pang feels delighted by this but his life is at risk when Shing learns of his illness. Fearing that Pang's business will fall in San's hands, Shing tries to kill Pang while San is still away at honeymoon.

Pang is seriously wounded and is under treatment in hospital. Shing sends his men to assassin Pang in the hospital but Han happens to visit Pang and saves his life. Afterwards, he tries to protect Pang. San, who is then in Macau, also gets the news that Pang is in hospital. Pang is suspecting that Shing is behind his assassination. 'his saddens him but instead of killing Shing, he sends him away making him promise never to return to Hong Kong. Shing has no alternative but to say goodbye to Hong Kong. Pang hands his business over to San and before he dies, he goes to see Han and Ying offering his forgiveness.

Life is not at all easy for Han and Ying whose family keep asking them for money. At work, Han is also ill-treated by the foreman. Han puts up with all these and keeps working hard. To help his friend, San goes to warn the foreman to be good to Han whose connection with the underworld is disclosed。This drives his other colleagues away from him。 San invites Han to join the gang and help him. This meets strong opposition from Ying. In the end, Han refuses San，s offer. Ying longs to lead a peaceful life away from the conflicts. She urges Han to withdraw completely from the gang and breaks his connection with San. This greatly saddens San．It is only the news that Chuen is going to borne him a son that makes him happy again. Wah is infuriated when she learns that San is working in the underworld and is involved in bribing the police。

It is seven years later that the charity acts of San and his moving speech at the school's opening ceremony deeply touch Wah who pardons San. Shing runs into heavy debts overseas. The loan-sharks comes to ask San to repay his debts. San settles that and arranges Shing to work with Wai Bill. On the surface, Shing seems determined to reform but he is in fact waiting for the opportunity to do San away and take his place. Lung asks Han for protection money but Han refuses to pay. Lung intends to teach him a lesson. However, he finds Han and San together. Fearing that it will antagonize San, Lung dares not press Han anymore. However, when Lung's brothels are raided by the police, he puts the blame on 'San and decides to kill San and his son Chi Ho.

San and his son escape from being killed. After this, Chuen urges him to withdraw from the gang and switch back to legal business. San also gets tired of such a life and decides to leave the gang in five years. This delights Lung but makes the other gangsters feel being betrayed. Shing gets hold of -- this opportunity and instigates them to go against San. To pacify the gangsters, San denies that he wants to leave the gang. At the same time, he suspects Shing to be behind the whole plot, so he asks Han to keep an eye on Shing. At first Han is delighted to know that San decides to switch back to legal business. He tries to help them make the arrangement. However, when he learns that the gang will not let San go, he joins hands with San to fight for survival against the underworld even refusing to go overseas with Ying who in the end leaves for abroad alone.

Shing finds himself watched by Han and cooperates with Lung to trap Han. In the end, Han kills Lung and injures Shing while he himself is also wounded. Ying misses Han and returns. She is shocked to find him wounded. The two hide in a deserted house and Ying goes to inform San of this. San and Han decides to kill Shing who has done them much wrong and even once plotted to kill Pang. Chi is killed while he is investigating a bribery case in which people from the police and the underworld are involved. Shing in fact shots Chi with San's gun. So San is arrested and charged for murdering Chi.

San is sent to jail and is waiting to prove his innocence. Shing takes his place and meets little opposition. Han and other faithful followers of San arranges to rescue San from the prison. Chuen, Ho and Ying are to meet Han and San at the pier but when they are leaving, they are stopped by Shing who locks them up. Han successfully saves San but cannot find Chuen or Ying at the pier. However, they are attacked and chased after by Shing's men.

San and Han manage to escape and kill Shing's men. But they plot to pretend that they have been killed already. Learning of their husband's death, Chuen and Ying feel very sad. Thinking of the safety of her son Ho, Chuen dares not go against Shing. However, Ying in her anger tries to kill Shing as a revenge but in the end she herself is killed. Shing uses the life of Ho to threaten Chuen and forces her to marry him. Chuen can do nothing but to do what he says. Yet she makes him promise to send Ho overseas first before they ,join in marriage. When Han learns of Ying's death, he decides to avenge on Shing. San agrees to give him a hand. They plan to kill Shing on the day of Ho's departure. However, Shing is quick to notice that and takes Chuen as a hostage. In the end, after a fierce fight, Shing is made to pay his due.