S1, E1: Series premiere. San Francisco, 1878. Ah Sahm, a newly arrived Chinese immigrant with serious fighting skills, is introduced to Chinatown's most ruthless tong, the Hop Wei. After impressing Young Jun, son of tong leader Father Jun, Ah Sahm is branded and taken to the local brothel, where he befriends Ah Toy, a courtesan with connections. Later, in search of a woman who left China two years earlier, Ah Sahm crosses paths with Mai Ling and Li Yong, followers of the rival tong leader Long Zii, who is trying to avoid an opium war with the Hop Wei--a war that Walter Buckley, the deputy to San Francisco Mayor Samuel Blake, actively promotes. Meanwhile, after two Chinese laborers are killed by white thugs, police sergeant Big Bill O'Hara is tasked with creating a Chinatown squad. Enlisting a southern-born cop named Richard Henry Lee, Bill soon finds that the hostility between the Chinese and white dock workers is unlikely to end anytime soon.