The first three films starred Tao Dayu and Guo Keying.
Zhang Dayong is from the West Kowloon Crime Squad.
A **** 100 episodes.
The titles of the dramas introduced in the Mainland are different, based on 20 episodes:
"Criminal Detective Files 1"--"Criminal Detective Files"
"Criminal Detective Files" File 2
"Criminal Investigation File 3" - "Invincible Pioneer" and "Urban Detective"
100 episodes in one ****.
"Criminal Files 4" stars Louis Koo, Xuan Xuan, Chen Jinhong, and Charmaine Sheh
It has no connection with the first three movies. It tells the story of the Central Police Station.
The story of Louis Koo and Xuan Xuan is very touching.
Personally, I recommend watching the first three movies, which are related to investigation and solving crimes, and the plots are relatively compact
.