In 1900’s San Francisco, a white woman is murdered in Chinatown and the suspect is a Chinese man. The murder causes a social shock and the public calls for Chinatown to be outlawed. Chinese medicine practitioner Qin Fu and Chinese man Ah Gui are involved in the case, and they race against time to find the murderer amidst a battle of wits and courage. 《唐探1900》的故事发生在1900年的旧金山唐人街,一位白人女子在唐人街被害,而嫌疑人正是一名华人男子。这个案件不仅引发了社会的动荡,更使得唐人街面临着被取缔的危机。在这样的背景下,中医秦福和华人阿鬼卷入了此案,他们必须在斗智斗勇中找到真凶,揭开真相。