With the Stone Wars over, Tsukasa's former Empire of Might has merged into Senku Ishigami's Kingdom of Science, and the combined group turns its energy toward building an ocean-going ship. Their destination is Treasure Island, where Senku's late astronaut father Byakuya once lived and where Senku believes the source of the global petrification ray can be traced. The crew arrives to find a community that has weaponized petrification to enforce a violent order, and the platinum critical to Senku's plans held by a hostile island ruler.