As the bubonic plague spreads through Italy, a group of nobles and servants retreats to a villa, where their lavish getaway quickly spirals into chaos.
Living in Ikebukuro — an area infamous for juvenile crime, 21-year-old Makoto Majima becomes associated with a youth gang called the G-Boys. A troubleshooter known for his cool headedness and ability to get things done, Makoto diffuses tense situations around Ikebukuro to keep his friends and others out of harm's way. However, the mysterious death of his girlfriend and an escalating gang turf war threaten to be more than Makoto can handle.
Upon discovering ancient stones with dinosaur images imprinted on them, a 12-year-old boy named Max Taylor (Ryuta Kodai) and his friends Rex Owen and Zoe Drake (Malm Tatsuno), discover they are able to call forth dinosaur companions. These companions will aid the owners in stopping the nasty Alpha Gang from coming into possession of the mysterious stones and crush their chances at world domination.
Three people's fates are interwoven in the Battle of the Teutoburg Forest in 9 A.D., during which Germanic warriors halt the spread of the Roman Empire.