20th Century Boys (Nijusseiki Shōnen) is a manga, or Japanese comic, that was created by Naoki Urasawa. Urasawa graduated college with an economics degree but decided to pursue his passion: manga. E has created quite a few popular manga, some of which have run a long time. 20th Century Boys was first published by Big Comic Spirits in 2000, and ended its run in 2006. A live action movie of 21st Century Boys is in the works to be released in 2008.
Endo Kenji is growing older, and is realizing that he doesn't like it. He discovers that his niece is missing, and that there is a conspiracy that is occurring in the world. There are deaths that are being tied to Ochanomizu University, and a mysterious "friend" appears out of Kenji's past in order to help him solve the problem.
There are four different time arcs in the series. The first is in the sixties, when Kenji, Otcho, Yoshitsune and Maruo are very young. They hide out, look at porn magazines and talk. Otcho draws the symbol to represent their base, and their friendship. They start imagining what life will be like when they grow older, an they dream about a giant robot that comes to destroy Tokyo. A boy named Fukubei follows them and finds the story, which they have written down. He adds to the story, bringing in germ warfare.
In the 1970's, Kenji and the others are talking about going to the Osaka World Expo. Instead of going there, though, Kenji is taken to the family beach house for the summer. It turns out that none of the kids made it to the Osaka World Expo.
Later, in the eighties, they go to separate colleges. Kenji begins a band and runs his family's store, while Yukiji runs his grandfather's dojo. Ochto gets married, and eventually has a son. He chooses to focus on business, though, and is devastated when his son is killed in a car accident. He leaves and heads into the jungle, taking some time to train with a monk.