When it opens, Avatar: The Last Airbender is a very simple show. The opening titles tell the whole tale: the world’s at war, and the Fire Nation (the bad guys) want to conquer everyone else (the good guys). Only one person, the Avatar (the hero) can stop them, and as luck would have it, he just showed up and he’s ready to fight. Of course, he has challenges: he’s been gone for a hundred years, he hasn’t mastered his powers, and he’s an immature little kid. But that’s okay; that’s interesting. Watching him make his Hero’s Journey sounds like a hoot.

Of course, as my kid and I have watched Avatar – we’re halfway through the last season – we’ve learned more and more about how this world works. In the first episode, the characters’ “bending” looks magical: you wave your arms and water floats or fire shoots or the air turns into a tornado. But as the show goes along we learn that it’s more like a martial art, requiring massive skill and discipline. We learn about the four elements and what they signify, in terms that match the characters we’ve met: fire, like Prince Zuko, is destructive and tough to control; earth, like Toph, is stubborn and stands its ground. We learn about politics in the Fire Nation. We pick up the history of the previous avatars, and meet the last two to hold the title. And the Earth Kingdom’s capital city, Ba Sing Se, plays a major role in the second season – but as far as I remember, we first hear the name when it’s dropped into conversation. The show has a rich backstory, but we only learn about it when we need it.

When we talk about worldbuilding, it’s easy to assume we’re talking about something really heavy and excruciating. Blame it on Tolkien: ever since he gave Middle-Earth dynasties, legends, and even its own made-up languages, the bar has been set high for “lore.” I know that my own childhood experience of reading the first three pages of Silmarillion gave me the idea that your made-up little story is lightweight if you don’t have a linguist on staff.

At the same time, most of us like things simple. Your decision to make an investment in a game, book, comic, or what have you, depends on whether the first few minutes make you care. And Tolkien apparently got that, too; as my dad once put it, that’s why he has hobbits.

Avatar’s world is rich, but never complex – and that’s what I like about it. And here’s the thing: thinking about Avatar, or Star Wars, or a bunch of my other favorite works, has made me think that simple is good. Give me a world, but give me a good guy and a bad guy. Keep the details in a shoebox until I really need to see them. Don’t do what they did in Mass Effect, where you have some computer encyclopedia with tons of stuff from your story bible that you crammed in there because hey, maybe five different people will read it someday. Why would you ever make things so hard?

And then I remember The Wire.

Sometimes, you want a world that gives a meaningful backdrop to a long-running story. And sometimes, the world is the story. If you’ve ever watched HBO’s five-season masterpiece, you’re probably know it’s a little complicated. There are dozens of characters, all of them morally complex. You’ll have trouble picking out a “protagonist.” There are clear conflicts in the story, but no clear resolutions, which fits the show’s vision. The city is a broken system, and we see all the reasons that noone can fix it.

Fans of The Wire revel in its complexity, but it didn’t come from nowhere. David Simon and his team built on many other works – Simon’s reporting on both the police and the drug dealers led to two earlier books that both became TV shows, and seeing Homicide and reading The Corner prepared me for what he was doing in The Wire. The Wire just does it better, and does it all at the same time.

Even a casual viewer can latch onto all the familiar cops-and-criminals tropes. Both white and blue collar workers, no matter how boring their jobs are, will see their own frustrations reflected in the storylines. You don’t need hobbits here, because all adults can see themselves somewhere in this show.

But more than Avatar, we’re drawn in by the entire world that we’re given – a system where tiny details have big impact, where a chance encounter in one season can pay off in another, where characters from all walks of life have a chance to change each other, and only the audience and the author get to see the whole picture. We want all the things that are only possible in a world this big.

I could probably write 20,000 words on the show and about 20,000 other people already have. But I guess what I’m getting at is that The Wire‘s complexity works because The Wire is based on real life. A fantasy world could grow into something just as complicated, but to make people care, you’d have to throw in some hobbits. And even then, you’d risk ticking off your audience. Imagine if someone made up a world that was as frustrating as The Wire‘s. Wouldn’t you hate the writer of that show? You’d want to know why they were thwarting their characters, why they made a clear win impossible, and why they’re not seeing a shrink like right damn now. You’d start to wish there was a hero – a really straightforward one, like the Avatar and his gang. And it would baffle you why they couldn’t just go out and save the day already.