Big Comic Original
Written and illustrated by Naoki Urasawa, "Monster" was published in "Big Comic Original" from December 1994 to December 2001. The 162 chapters were periodically collected into 18 tankōbon volumes published by Shogakukan, the first on 30 June 1995 and the last on 28 February 2002. While writing "Monster", Urasawa began the series "20th Century Boys" in 1999, which would continue after "Monster" had finished.