
One Piece: Ocean's Dream is a Japanese board game for PlayStation that supports both single-player and multiplayer modes, inspired by the popular One Piece manga and anime series. Developed by 8ing and Q Entertainment, it was published by Bandai Namco. The game's story was later adapted into a filler arc of the anime known as the Ocean's Dream Arc, which closely followed the game's plot. It was launched in May 2003.
One night, as all the Straw Hat crew members—except Robin, who was engrossed in a book—slept in their bunks, they all shared a dream of a hooded young man playing hauntingly beautiful music on a sea horn beneath the waves. The next morning, the crew awakens, and Robin is stunned to learn they no longer remember her or their time as a Pirate Crew. Their minds now hold only the memories from before they joined, and the crew begins to fall apart. Nami flees the ship with all the treasure, having returned to her old ways as a pirate-hater and thief, while Zoro clashes with the others and departs, convinced he's once again a bounty hunter. Now, it's up to Robin to bring the crew back together, help her friends recover their lost memories, and uncover the source of their strange amnesia.