Having started to watch the excellent David Simone show The Wire for the first time last week (I'm now in Season 4, if that gives you any idea of how much time I spend watching it). The complexity of the show stands out as a beacon in the night of television; The Wire has effectively created a city of its own, a mirror-Baltimore that has its own ins and outs. What does this mean for D&D? I've been thinking about that and, after some study and serious pondering, I believe that The Wire has a lot to teach us about making realistic cities in Dungeons and Dragons.
1) Cities are complex. This can be extended out to any organization. The amount of infighting, backchannel backstabbing, and political faction-playing in the show is a great lesson. Adventurers are generally hired by someone right? The people who hire them are, generally (at least in my experience), given little more fleshing out than the police department in a regular cop drama. I have tried my best over the past few years to make sure every job is charged with consequence, with political backlash. After watching The Wire I have a thousand more ideas on how to detail the people (and organizations) that hire adventurers.
2) Shit is difficult to accomplish. This translates less to D&D because the organizational inertia which prevents the successful accomplishment of various police tasks doesn't necessarily exist in a fantasy world. In a medieval world there are few institutions that can drag you down in that manner—but that doesn't mean that political interests can't do the same. Of course, The Wire is a show and D&D is a game: you don't want to prove to the players that it is always or even generally impossible to succeed due to institutional (or in this case perhaps political) circumstances. That would quickly get demoralizing. However, the option should always be there and I personally like to draw out unforeseen consequences of even the most goodly acts.
3) Characters aren't good or evil. Uh oh, the ALIGNMENT TALK. Here again, I'm not saying that good or evil are not applicable. Good and evil, in alignment terms, are descriptions of the way a character behaves. But, as The Wire teaches us, no one always behaves in a certain way all the time. Alignment lenience here is important. Not every Lawful Good man's actions are going to be lawful good forever. That doesn't mean that, because of a few breaks with alignment, that you're alignment is going to change. Of course, consistent breaks speak of a character change. So here I don't mean characters aren't good or evil (in terms of alignment), what I mean is that people aren't bad people or good people.
4) People have long memories. Chances are, if adventurers screw with someone at some point, that person will remember. Sometimes, you do something nasty to a local knight only to discover that he's been named the Seneschal of the Emperor. This stuff sticks with you. Conversely, do a good turn for someone and you never know when they might turn up again to help you out.
5) Everything is connected. The crime network in The Wire is contiguous, connected, and spreads like an insidious cancer throughout every organ of government in Baltimore. Why should crime in a fantasy city be different? Everyone is connected to everyone else, somehow. It's the DMs job to figure out how they are and the PCs to exploit it (or be exploited by it).