The "Complete Edition" of Naoki Urasawa 's 21st Century Boys manga will include a new ending specifically created for the publication. Shogakukan will publish the 418-page volume, which compiles the complete series with color pages, on December 28 in Japan.

The manga is a follow-up to Urasawa's earlier 20th Century Boys manga. Shogakukan originally published the series in two compiled book volumes in 2007. Viz Media published both volumes in English in 2013.

Viz Media describes the manga's story:

War is over. The Friend is dead. Mankind no longer faces the threat of extinction. Peace has finally come to Tokyo... or has it? The mystery still remains. Nobody knows who the Friend was and where he came from. The only clue is hidden deep within the memories - the memories of the hero Kenji. It is time to open Pandora's Box to discover what is left at the bottom.