The comic-book world is no stranger to superhuman events, with good and evil as easy to spot as the grinning-skull logo on your tights.

But when comic-book violence came to the real world — only blocks from the headquarters of the world's two major superhero factories — the brightly colored world of Superman and Spider-Man shuddered.

"When hell hit the World Trade Center, most of us stood around talking, making phone calls, writing e-mails, and generally filling in that hole in our bellies with meaningless chatter," Marvel Enterprises COO Bill Jemas wrote in an e-mail interview. "But in the face of extreme danger, thousands of New York firefighters, police officers and rescue workers burst onto the scene."

These real heroes served as a source of inspiration for many of the artists at Marvel. And over at DC Comics, the home of Batman and Clark Kent, the reaction was similar.

"There was a wonderful story that a writer [here] wrote about a father-and-son artist team in their studio as the towers come down, and the son asks, 'How can I just write funnybooks?'" DC Comics Executive Vice President and Publisher Paul Levitz said in a telephone interview.

At both comics houses, artists and writers banded together to put out special books of collected stories and art dealing with the tragedy, some focussing on the police officers, firefighters and rescue workers who rushed to the scene, others on how regular folks dealt with the news.

DC's two-volume book is entitled 9-11, and is hitting stores next week. Marvel published Heroes and Moment of Silence, which deals with Sept. 11 without words, and is auctioning off some of the artwork. The proceeds from both the DC and Marvel books will be donated to charity. Heroes sold 100,000 copies in the first two days alone when it came out in mid-October.

In one of the 9-11 stories, writer Steven T. Seagle and artists Duncan Rouleau and Aaron Sowd take on the first question anyone would have asked in Metropolis: Why didn't Superman, the most powerful well-known superhero, prevent the tragedy?

"As writers, you had to deal with the question of how do you deal with the boundaries between the omnipotence [in a fictional world] and helplessness [in the real world]," said Levitz, who was the editor of the books. "In the story … Superman can do these wonderful things but bemoans his inability to leave the printed page and affect the real world. But he's thankful there are real heroes."

Instead of looking at the tragedy through mutant or gamma-radiated eyes, Marvel's Heroes centers around the personal experiences of those whose lives changed in the attacks, from the story of a team of firefighters who drove from Cleveland to help look for survivors, to how a New York City firefighter's widow explains to her children that their father is dead.

But after the tribute books, the Marvel and DC universes will have to go on — like people in the real world — without the Twin Towers. And it's still not clear what that means for crime fighters like Green Lantern or Daredevil. At both comics houses, the writers have been given leeway to deal with the issue according to their styles and their running storylines.

"We are giving our creators the freedom to explore or ignore the issues as they see fit," Jemas wrote. "Some of our writers have something significant to say about the issues at hand and Marvel wants to give them the opportunity to say it. Other creative teams work on books that have more to do with escapism than reality, and I would not mandate that they change that approach."

If there is going to be a lasting effect from the tragedy, it's the lesson artists and writers learned about heroism, Wolverine artist Sean Chen said.

"After what happened on Sept. 11, what the firefighters, police officers and rescue workers did their true acts of heroism inspired what we do with our superheroes," Chen said. "Seeing what they did raises the bar for what we do, and hopefully inspires the call in people who read our comics."