So, I generally dislike Chinatown episodes.
They always involve "the triad" and people smuggling. It's like Chinese people don't know how to do anything else when they're not doing Kung Fu. It didn't help that there was some widely varying degrees of Cantonese proficiency throughout the episode. I think Peter's Cantonese was better than some of the "Chinese" character's Cantonese.
Still, at least it worked well for what it was. The triad was pretty much non-existent, so they didn't have any chance to act "Chinese" - the dude who played the evil scientist was also on Cold Case speaking stilted Confucianisms a few weeks ago - and I actually enjoyed the moment between Walter and the Chinese lady. It was just unexpected. Although, kind of weird that he was in a silk robe though.