San Francisco, early 1900s. A white woman is murdered in Chinatown, and a Chinese man becomes the prime suspect. The crime causes widespread public outrage, and the townspeople demand that Chinatown be closed. The case is investigated by Qin Fu, a traditional Chinese medicine doctor, and A-Gui, a Chinese-Indian hunter.

While investigating the details of the bloody deeds of an unknown killer, Detective Eric Matthews catches himself thinking that they are very similar to the work of Jigsaw, a notorious maniac who managed to disappear, leaving behind many victims. Matthews turns out to be right. Jigsaw has once again taken up his gruesome trade. Only this time instead of two people, he locks eight people in the room of death with the only way to get out alive. Eight strangers are forced into a game of crazy killer, the stakes of which will be their lives.