The Los Angeles of “Crash,” a moody drama of intersecting characters and stories, is an exaggerated one in which everybody is racist. Whites, blacks, Latinos, Asians and Middle-Easterners, all ethnicities hold prejudices against all the others. The movie doesn’t say it’s right or wrong, necessarily — one character’s judgment of a Latino turns out to be inaccurate, while her fear of two black men is justified — only that it IS, and that it can get in the way when people must interact with each other.

The action takes place over two December nights in L.A., as several stories are established so that they can collide later. The district attorney (Brendan Fraser) and his wife (Sandra Bullock) are carjacked by two black men, Anthony (Chris “Ludacris” Bridges) and Peter (Larenz Tate). Anthony is the senior, fight-against-the-White-Man partner, while Peter is young and naive enough to believe they are stealing because it beats working, not because white society has forced them into it.

Across town, a black detective (Don Cheadle) and a Hispanic one (Jennifer Esposito), partners and occasional bed buddies, are called to investigate an incident where an undercover white cop has shot an off-duty black cop. The shooting may have been justified … but then, this guy has already shot three other black people in his career….

Then there is the black TV director (Terrence Dashon Howard) and his light-skinned black wife (Thandie Newton) who are pulled over and harassed by the piggishly racist Officer Ryan (Matt Dillon), whose youthful partner (Ryan Phillippe) objects but is powerless to intervene.

I will also mention the Hispanic locksmith (Michael Pena) with an adorable 5-year-old daughter; and the Persian family, often mistaken for Arabs and thus for terrorists, who buy a gun for protection at their downtown business; and then the cast of major players is complete.

The movie, directed by “Million Dollar Baby” writer Paul Haggis (his first time behind the camera) and written by him and Bobby Moresco, treats Los Angeles like an ant farm, shaking it up so we can watch everybody scramble and fight. Accordingly, we aren’t much attached to any of the specific ants, seeing them the way Haggis portrays them: as types and figures, not as real people. Their stories, while often interesting and even compelling, feel more like mini-lessons than plots.

I also note that many of the problems between the characters come as the result of miscommunication — not the real-life kind, but the movie kind, the kind that would be easily solved if the characters would just talk the way real people talk. Humans are much more direct than these people are. We say what’s on our minds, especially when it becomes apparent that the person we’re talking to is forming a wrong impression.

The film’s real message isn’t anti-racism but pro-screenwriter. “Look how many coincidences we can pile up!” it seems to say. “Look at how these stories all interlock!” For as much as it wants to be a gritty, less mystical “Magnolia,” it relies too much on unbelievable coincidences: the cop who persecuted someone later having to rescue her from a burning vehicle; the murder victim being discovered in a field by his own estranged brother; the nurse who helps identify the body being the daughter of the Persian shopowner. They come quickly and outrageously in the movie’s final 20 minutes.

One major bit of extraordinary happenstance can be the crux of your plot, but when you stack up dozens of them, it feels contrived. While Haggis’ screenplay for “Million Dollar Baby” was exceptional for being unobtrusive, “Crash” is the opposite, full of grandstanding and showboating that detract from what could have been an insightful, powerful film.

C+ (1 hr., 52 min.; R, abundant harsh profanity, a little nudity, some brief sexuality, a little violence.)