Los Angeles and Environs, 1937
Too Much for the Man
Gladys Knight once sang the line, "L.A. proved too much for the man." In Chinatown, L.A. proves too much for Jake Gittes, despite all his tough detective work.
It turns out these perpetually sunny skies and orange groves are surrounding a den of iniquity, a place seething with corruption and dark secrets—like greed, murder, and incest.
That being said, the Greater Los Angeles area in 1937 still looks pretty good. There are some nice pastoral landscapes nearby (featuring all those orange groves), pretty sunsets, there's no nightmarish L.A. freeway system, and the city hasn't become choked with smog. It's a healthy, pretty place—it's La-La Land.
But the secrets that lie beneath this pleasant facade are pretty freaking terrible. And those secrets frequently involve the rich and powerful ripping off everyone else.
Trouble in Paradise
According to Professor Ewa Mazierska's book on Roman Polanski's films, the movie's version of L.A. indicates that only the elite can afford to live the SoCal dream life that so many people desire:
Hollis Mulwray's estate looks like a rustic paradise with ponds, porches, and gazebos. However, the fact that it belongs to one of the richest families in the town makes us realize that only the minority of the town's population enjoys the paradise. Wherever Gittes goes, he sees signs reading "private property" or "no trespassing," and eventually he is beaten up when he enters somebody's orchard. (Source: Ewa Mazierska. Roman Polanski: The Cinema of a Cultural Traveller. I.B. Tauris: 2007. 79.)
This is all true—although when Jake enters the farmer's orchard, he's beat up because they suspect him of being an operative working for the water department, which is in the process of cheating and terrorizing all the farmers.
So, the greed of the water department has infected these peaceful orange groves with a violent strain of suspicion—it's justified, but totally out of keeping with the pastoral landscape.
With the retirement home Noah Cross is using to mask his water theft scheme, we see the same thing in process—on the surface, it looks like a peaceful old folks' home, but it's actually being manipulated to serve the forces of greed.
Wait…Where's Chinatown in this Movie?
We don't actually see L.A.'s Chinatown until the end of the movie. And even when we do, it's not totally obvious as a Chinatown. Unlike Chinatowns in San Francisco or New York, there's no fancy gateway or sign proclaiming, say, "Now Entering Chinatown, Home Of The Most Delicious Food In The City."
(Man. We could really go for some soup dumplings right about now.)
In this Chinatown, it looks like there's just some Chinese signage on the buildings. We don't actually see any prolonged interaction between Jake the Chinese population.
What's crucial about the location, though, is that it helps establish Jake's character arc. He left being a cop in Chinatown in order to escape the confusion of dealing with a culture he didn't understand…and rid himself of the frustration of failing to help people.
Now, the same thing is happening again—except, in this case, it's his failure to understand the nature of Noah Cross and Noah's culture of corruption that's defeated him. That's right: the evilness of Noah Cross is even more incomprehensible to Jake than trying to do business in a foreign language.
Blood for Water
Strangely enough, the events in Chinatown are partly based on real historical events. In Southern California in the 1920s there were a series of disputes of water rights known as the "California Water Wars."
There was a controversial dam-building project led by William Mulholland—whose name is intentionally similar to Hollis Mulwray's—which ended in the collapse of a dam and the deaths of many people. (Source)
The movie switches the time frame to the thirties, but the fact that this is based on something real makes the movie's atmosphere more affecting. We know that things like water theft and institutional corruption really do happen, so when incest enters the picture we have to confront the fact that something so disturbing also fits into the world that we all inhabit.