Can you believe that in Guizhou, a 17-year-old girl was raped and murdered in her own home, but it was five police officers who were ultimately sentenced? Did the real culprit go unpunished? Buying a house, a car, getting married, and having children—this was the news story that topped a certain website's annual rankings in 2018. Now, it has been adapted into the movie "The Lonely Warrior," based on this shocking real-life case.

However, all the work Cheng Bing did had a common characteristic: he would come into contact with numerous strangers, and his work locations and areas were not chosen randomly. He was searching for someone, someone he hadn't found yet—Wang Er Yong. Even while still in prison, Cheng Bing would often unintentionally and intentionally communicate with fellow inmates who were thieves, gathering clues. After being released from prison, Cheng Bing went to Guizhou and found a job as a courier.

Six months later, Cheng Bing went to Chongqing and worked as a taxi driver for five months. He drove every day, becoming familiar with the streets and skillfully inquiring about everything he wanted to know from his passengers. After five months, armed with new leads, Cheng Bing quit his job and started working as a truck driver for an air conditioning company in Chongqing.

He only lasted two months in that job before resigning and going to Sichuan. In Deyang, Sichuan, he found a residential complex and successfully applied for a position as a security guard. During the seven months he worked as a security guard, he diligently recorded information about people and vehicles entering and exiting the area. This was to obtain a comprehensive understanding of the entire community, although it was for the purpose of investigating the case. Cheng Bing was thorough in every job he took.

When he obtained new leads again and was ready to quit, the property manager tried to persuade him to stay and offered him double the salary to become the chief security guard. However, Cheng Bing still left. This time, he went to Yiyang, Hunan, and became a network administrator in an internet cafe near Hunan City University. After six months, he went to Changsha and became a truck driver again, using the most primitive methods to search for a suspect hidden among the vast population.

After six months in Changsha, Cheng Bing received news and returned to Guizhou. This time, he chose a completely new industry: water delivery worker. Cheng Bing carefully observed and interacted with the residents in a friendly manner. Everyone liked this kind and diligent water delivery worker. One day, the owner of the water station discovered Cheng Bing's notebook, filled with detailed information about his water delivery customers, including their names, ages, phone numbers, and even their schedules and financial situations.

The owner of the water station felt something was not right and immediately questioned Cheng Bing. Cheng Bing explained that recording names and ages was for addressing customers during phone calls, recording schedules was to avoid delivering water when no one was at home, and recording financial situations was to provide better service. The water station owner believed Cheng Bing's explanation without a doubt because since Cheng Bing started working there, the water station's revenue had increased by fifty percent.

Wang Da Yong's head injury was likely sustained during the scuffle with the victim's family, but even so, The Lonely Warrior couldn't escape punishment. When the two families of the victims learned about this, they even knelt at the doorstep of the prosecutor's office, pleading for leniency for The Lonely Warrior. However, the law remained impartial, and the prosecutor's office proceeded with the case according to regulations.

In The Lonely Warrior, Cheng Bing received the harshest sentence of eight years, the shortest sentence was four years, and the longest was twelve years. The other individuals involved were also stripped of their police uniforms, although they did not receive prison sentences. Deputy Director Yang, who was in charge of The Lonely Warrior case, resigned from his position, leading to a long life behind bars.

Once the officers who used to investigate and sentence them, they now became prisoners themselves, subjected to the aggression of others. We don't know about their lives in prison, but we can imagine. The Lonely Warrior case was passed on to other criminal investigation teams, but there has been no effective progress. Cheng Bing was released from prison in 2009, and his difficult life did not extinguish his determination.

The department knew about his financial difficulties and wanted to arrange a job for him, but Cheng Bing refused.

Before going to prison, he also divorced his wife, and his daughter went to his wife. The current Cheng Bing is completely different. From 2009 to 2013, he traveled through Hunan, Sichuan, Chongqing, and Guizhou, doing various laborious jobs such as selling goods, taxi driving, moving heavy objects, being a courier, and even working as a security guard and gatekeeper.

But all the jobs he did had one thing in common: they involved a lot of contact with strangers, and the locations and areas where he worked were not chosen randomly. He was looking for someone, that person he had never been able to find. Wang Eryong. Even when Cheng Bing was still in prison, he would often unintentionally exchange information with fellow inmates who were thieves. After his release, Cheng Bing went to Guizhou and found a job as a courier based on the clues he had obtained.

Six months later, Cheng Bing went to Chongqing, where he worked as a taxi driver for five months. Every day, he drove through various streets and skillfully inquired about everything the passengers wanted to know. After five months, Cheng Bing received new clues and quit his job to join a truck driver position at an air conditioning company in Chongqing.

He only worked in that position for two months before resigning and going to Sichuan. In Deyang, Sichuan, he found a residential area and successfully applied for a security guard position. During the seven months as a security guard, he diligently registered the information of people and vehicles entering and leaving the area. This was to have a grasp of the entire community's information, although it was for the purpose of investigating the case. Cheng Bing took every job seriously.

When he obtained new clues again and was preparing to resign, the property manager tried to retain him and offered him the position of security team leader with double the salary. However, Cheng Bing still resolutely left. This time, he came to Yiyang, Hunan, and became a network manager at an internet cafe near Hunan City University. After half a year, he went to Changsha and became a truck driver again, using the most primitive methods to search for a suspect hidden in the vast sea of people.

After staying in Changsha for half a year, Cheng Bing received news again and returned to Guizhou. But this time, he chose a completely new industry: water delivery worker. Cheng Bing carefully observed during the water delivery process and had friendly conversations with the householders. Everyone liked this kind and hardworking water delivery worker. One day, the owner of the water station found Cheng Bing's notebook, which was densely filled with information about his water delivery customers, including their names, ages, phone numbers, and even their schedules and financial situations.

The owner of the water station felt that something was not right and immediately questioned Cheng Bing. Cheng Bing explained that recording names and ages was for convenience when making phone calls, recording schedules was to avoid delivering water when no one was home, and recording financial situations was for better sales strategies. The water station owner believed Cheng Bing's explanation without a doubt because the water station's revenue had increased by 50% since Cheng Bing arrived.

After working as a water delivery worker for nine months, and after repeated confirmations, Cheng Bing finally confirmed the identity of Wang Eryong. When Cheng Bing knocked Wang Eryong down to the ground, Wang Eryong had no idea that the delivery worker who had visited him multiple times was actually Officer Cheng, who had been imprisoned twelve years ago because of his brother's death. Since his brother's death, Wang Eryong knew that the police would not let him go, so he lived in constant fear, constantly hiding and changing his name, spending money to obtain fake identity cards. He didn't dare to steal again, and he didn't even dare to drink alcohol for fear of saying something wrong while drunk.

Even when he was being bullied outside, he endured it, fearing that it would attract the attention of the police. Despite his caution, he was eventually found by the persistent Cheng Bing. In fact, in Chongqing, Cheng Bing almost found Wang Eryong. Wang Eryong had worked as an installer in an air conditioning shop in Chongqing because of his previous experience and good skills. The company wanted to sign a long-term contract with him.

But people like Wang Eryong couldn't stay in one place for long, so he immediately gave up the job. On the day he quit, it was the same day Cheng Bing started his job as a driver.

Wang Eryong, who was taken to the police station, knew very well that he couldn't escape this time. Faced with the evidence provided by the police, Wang Eryong finally admitted to the crimes he had committed.

On the evening of August 22, 2002, after his brother Wang Dayong and his wife left, Wang Eryong climbed up to the fourth floor through the air conditioner vent and began to commit burglary. Thinking that there was no one at home, they made a lot of noise while rummaging through the drawers and cabinets. Suddenly, the lights turned on, and a little girl who had just woken up in her pajamas saw them. The two of them screamed loudly, and Wang Dayong went up and covered the girl's mouth. The frightened girl fainted on the spot.

They quickly packed up the things they had found and were preparing to leave when they saw the girl lying on the ground with a healthy complexion, which aroused their desires. Just as they were about to force themselves on her, the girl woke up and began struggling and shouting loudly. In desperation, the two of them grabbed a sword-like ornament and repeatedly struck the girl's head until she stopped moving.

Who was the one who delivered the fatal blow? Wang Dayong said it was Wang Eryong, while Wang Eryong claimed it was Wang Dayong. The blood fingerprints of both individuals were found on the sword-like ornament, indicating that both of them were involved. In the end, Wang Eryong was sentenced to death with a reprieve, and this long-delayed justice finally arrived after twelve years. When Cheng Bing saw Wang Eryong being sent to prison, he let out a long sigh of relief. He had finally completed the mission of "The Lonely Warrior," a burden he had carried for twelve years.

He could finally live a normal life. The current Cheng Bing remarried his wife and opened a youth interest class in Beijing, leading the simplest and happiest life. Twelve lonely years were spent in search of justice. He sincerely hoped that justice would prevail in all unsolved cases one day.