its a martial arts drama that takes place in late 1800s san francisco, focusing on the Chinese gangs of Chinatown, as they try to coexist with each other, as well as the Irish immigrants and police. Its seriously one of my favorite shows ever.
If you havent seen it I HUGELY recommend it. It was cancelled after its third season, but with it coming to Netflix theres hope that high enough viewership will get us the 4th season.