A missing police pistol is connected to a series of recent heists and murders. Its owner Wong vanished earlier while pursuing a suspect in the mountains. His partner Chi-Wai miraculously returned unharmed. Hotshot Regional Crime Unit inspector Ho is in charge of the serial murder investigation.

He knows the only chance he has in cracking the case is to ask for help from his mentor/former boss Bun. Bun was recognized as a gifted criminal profiler until he went mad several years ago. Bun has the gift to see into a person's inner personality. This is where the subconscious desires, emotions and mental state are laid bare. For Bun, they are the key to unlocking a killer's identity. Bun comes to the conclusion Chi-wai has a total of seven personalities.

The cop's alternate identities are responsible for his murderous behavior. However, Ho feels betrayed when Bun's investigation went beyond his imagination. What begins as a quest for answers has now taken a schizophrenic turn where truth and lies, reality and delusions intertwine.

Directed by
Johnny To
Ka-Fai Wai

Cast
Ching Wan Lau - Inspector Chan Kwai Bun (as Lau Ching Wan)
Andy On - Inspector Ho Ka On
Ka Tung Lam - Ko Chi Wai (as Lam Ka Tung)
Kelly Lin - May Cheung
Kwok-Lun Lee - Wong Kwok Chu (as Lee Kwok Lun)
Choi-ning Lee - Gigi (as Karen Lee)
Flora Chan - Inspector Cheung
Siu-Fai Cheung - Violent Man (as Cheung Siu Fai)
Suet Lam - Fatso (as Lam Suet)
Jay Lau - Ko's Inner Personality (as Lau Kam Ling)
Eddy Ko - The Chief
Jo Kuk - Ho's Inner Personality (as Jo Koo)
Ling To Yuen (as Yuen Ling To)
Jonathan Lee - Weak Boy

Production Co.
Milkyway Image
One Hundred Years of Cinema

Produced by
Charles Heung
Wai Ka-fai
Johnnie To

Studio
First Take (IFC)

Writer
Ka-Fai Wai
Kin Yee Au

Music
Xavier Jamaux