Superheroes: A Never-Ending Battle, a documentary in three hour-long segments that will premiere back to back (to back) tonight on many PBS stations, begins with a curious image: Vincent Zurzolo of Metropolis Comics explains that a recent copy of Action Comics #1, which contained the first appearance of Superman, recently sold for over $2 million. He shows us Action Comics #1, and then ... he locks it in a safe.

It makes all the sense in the world: it's worth a couple million dollars. You lock it up. But locking it in a safe is an interesting image in part because it underscores what makes comics — and, more specifically, superheroes — a complex cultural phenomenon for a lot of people. As they've become more collectible, as they've become fetish objects, as they've become obsessions for their most ardent fans, they've become harder and more imposing for other people to wrap their minds around. And that's too bad, because comics — and, more specifically superheroes — make a marvelous lens through which to look at American popular culture more generally, even if you're not an enthusiast.

That's what Superheroes does well. None of what's here is going to be a big surprise to people who follow comics closely, but it's a fine three-hour tour of superheroes as an example for other people of the way popular culture is always in a dialogue with the other things that are going on around it.

In the evolution of superheroes over these three hours, you see the markings of immigration, World War II, the civil rights movement, the Space Age, censorship, feminism, corporatization of media, the evolution of print and the rise of digital, and the eternal nature of merchandising. You don't learn about superheroes just to understand how superheroes work; you learn about superheroes because it helps explain how everything in entertainment works and has worked for almost a hundred years. (This is also a recurring theme of Monkey See comics blogger Glen Weldon's book about Superman, by the way.)

There's a nice balance in the documentary between good and thoughtful placing of culture in context on one hand, and colorful stories on the other. Maybe you've heard all of Stan Lee's stories, but if you haven't, he's fun to listen to. The same goes for Jim Steranko, an artist who has maybe the best hair you'll see on PBS this year. (And that includes Downton Abbey.) And they speak pretty candidly at times — it's fascinating to hear one of the artists say he was always a pacifist, he always considered himself pro-civil-rights, but that when feminism came along, his first thought was that he should support it, rather than that he did entirely understand it.

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