What is the content of the movie "Lost Bullets"?

This is a suspense action movie, which mainly tells a bizarre murder case in an arsenal. The deceased was killed by "ghost bullets"-no bullets were found at the crime scene. For a time, doubts kept gathering and people were worried. This case is called the first mystery in the Republic of China. The case was investigated by Song Donglu (played by Liu Qingyun), a government policeman in charge of file management in the police station. Lao Dao, a civilian, is thoughtful and has a unique way to solve intractable diseases. Guo Zhui (played by Nicholas Tse), a hot-blooded detective who is bent on doing harm to the people, can't tolerate the corrupt atmosphere in the police station and joins hands with Lao Lu to investigate this bizarre murder case. .

How to shoot without bullets? How to make the bullet disappear after penetrating into the body? Lao Lu and Guo Zhui made various researches on guns and bullets, including firing salt bullets and ice bullets at pigs, but they didn't get satisfactory results. With the in-depth investigation of the case, the two detectives discovered the horrible murder chamber and the bizarre bomb-making device, which made the experienced old road stunned. Just when the truth of "Ghost Bullets Killing People" came out, Lao Dao, Guo Zhui and Xiaowu were killed one after another. The policeman Xiaowu (played by Jing Boran) was killed when he shot Lao Dao, and Guo Zhui escaped. The deadline for closing the case is approaching. Little lark (played by Yang Mi), a fortune-telling girl, inadvertently revealed the shocking secret of "Ghost Bullet". They don't know whether this "shocking secret" is a trap or a clue to solve the case, but they swear to fight with their lives! The case finally came out, but Guo Zhui and Lao Lu found that their respective fates had been mercilessly teased, and the choice of living only one was placed in front of them. ...