Imagine waking to a world where every last human has been mysteriously turned to stone...Senku, Chrome and Magma go spelunking for a rare mineral, but can they survive the dangers of a real-life treasure dungeon and make it back alive? They have no choice if they want to create the greatest “weapon” of modern times—the cell phone!Senku, Chrome and Magma go spelunking for a rare mineral, but can they survive the dangers of a real-life treasure dungeon and make it back alive? They have no choice if they want to create the greatest “weapon” of modern times—the cell phone!