One of my favorite television shows comes back today to start its final season. It's The Wire, created by David Simon and Ed Burns. Set in Baltimore, the series is one of the most realistic police dramas ever created, with a plot that weaves complications through many layers of characters and institutions.

Consider the fate of Sergeant Thomas "Herc" Hauk, who in the fourth season is facing disciplinary action in front of a review board. What Herc is technically in trouble for is misusing police surveilance equipment and attributing the resulting information to a non-existent informant. The reality is that no one cares about that.

What Herc should be in trouble for is his mishandling the situation with Randy Wagstaff, a juvenile source in a homicide investigation. While questioning a gang member, Herc accidentally gave away Randy's identity. Labeled a snitch, Randy was beaten and his home was burned down, putting his foster mother in the hospital with second and third degree burns. The reality is that no one cares about that either.

What's really happening to Herc is that he broke a couple of promises to Bubbles the junkie, so Bubbles decided to get a little revenge by giving Herc a fake tip about a drug mule. When Herc stopped the car that Bubbles described, he went off on the driver while searching it, only to find no drugs and to discover that the driver was a church minister and well-connected community leader.

Everybody cares about that. Before the season is over, the division commander, the Deputy Chief of Operations, the Police Commissioner, and the Mayor are discussing exactly how hard to screw Herc into the ground.

In the world of The Wire, Bubbles is a power to be reckoned with: Almost everything bad that happened to the Barksdale gang in the first season was ultimately because a few of them beat up one of Bubbles's friends.

Bubbles is a good example of the approach the series writers take to handling characters. Bubbles is a heavy drug user, hustling his way from one hit of drugs to the next, putting up with some truly awful shit. He looks like he smells bad.

And yet Bubbles is also very smart. It's not that he has some contrived backstory like he used to be a college professor before the drugs. He's just very good at living the kind of life he lives. Within his world, he's mostly very effective, and it's clear that in a different world he'd be a success.

That's one of the themes that runs through the series, that people who are successful in the streets aren't much different from people who are successful in the "straight" world of politics or government.

For example, drug kingpin Marlo Stansfield may have started as a corner drug dealer, but he knows how to manage people and he's not afraid to take advice from his trusted subordinates. He has a training program for his enforcers that includes pistol marksmenship and mock wargames fought in deserted buildings.

Marlo also plans for the future, and one of the things he's clearly planning to do is to go around double-dealing middleman Proposition Joe and get heroin directly from Joe's supplier. Joe, who has literally gathered about half of Baltimore's drug dealers into a co-op, will probably be coming up with some crazy scheme to stop that.

Bubbles, Marlo, and Joe are typical of the best characters of the series, at once very realistic and yet somehow possessing mythic qualities.

No character in the series is more mythic than street thug Omar Little, who has spent nearly all his life earning money by ripping off drug dealers. He's so dangerous and violent and smart that he's grown to mythic proportions within the story itself. When he walks down the street, children scatter before him and drug dealers surrender their money and drugs without daring to start a gunfight. They know that by the time they see Omar, they've already lost.

The way Omar sees it, however, he's not a bad guy. After all, he only rips off drug dealers, not the working people of Baltimore, and he's never shot someone who didn't have it coming. In some ways, he clearly thinks of himself as a kind of cop, even going so far as to snitch on drug dealers and testify against them.

Despite all these vivid characters, the show is actually driven more by plot and theme than by character. However, the show never seems to sacrifice its characters to serve the plot. The writers achieve this in a way I've never seen before: The Wire has a massive cast.

The HBO cast page lists 57 people, not including characters being introduced this season, and I can think of a few they've missed. With such a large supply of characters, the writers never have to advance the plot by betraying a character. Or the viewers.

If you haven't been watching the series, I'm not sure that this season will make any sense to you. I'd almost suggest you buy, rent, or steal the first four seasons on DVD to catch up. If you don't like it, you can quit during the first season, but if you do like it, you really should see the whole thing.

Finally, I've just got to get this off my chest: The characters in The Wire are every bit as real as in The Sopranos, but unlike The Sopranos, the writers of The Wire understand what a story arc is. Things happen to people for a reason, and if people change, it's because something changed them. The big dramatic moments are earned, and the interwoven storylines pay off in the end. It's not always neat, but there's always a reason.

The creators of The Sopranos usually explained their meandering pointless episodes---and their meandering pointless seasons---as being just like real life, which doesn't always have reasons. In this, The Wire is different. The Wire isn't real life. It's a story about real life.