Does the sunny superhero really need a dark side?

The ads for Spider-Man 3 are filled with gloomy imagery: a creepy black costume; Aunt May warning Peter Parker that "revenge is like a poison." "Every hero has a choice," the trailer warns. "To face the darkness, or be consumed by it." This downbeat tone is an odd one for a superhero who has long been distinguished by his total lack of a dark side. And the Spidey movie isn't the only version of Spider-Man's story treading this ground: Marvel Comics, the web-slinger's publisher, is taking Spidey in a darker, more violent direction, both in its regular series and in a splashy new miniseries. How did Spider-Man get to be a brooding vigilante?

Click here for a slide show about how Spider-Man got so dark.

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