The Straw Hat crew receives an invitation from the festival's promoter, , to join the world's biggest gathering of pirates. The main event is a high-stakes hunt for a lost treasure that once belonged to the King of the Pirates, Gol D. Roger .
: Led by Admiral Kizaru and others, the Marines initiate a "Buster Call" to wipe out the pirates in one fell swoop.
As pirates from across the globe—including the Worst Generation—converge to find the treasure, the festival turns into a chaotic "stampede" due to two main threats: