The special will revisit the childhood past of the three sworn brothers Luffy, Ace, and Sabo, when they all dreamed of becoming pirates. In addition, it will depict how Sabo originally came into the kingdom of Dressrosa (which was not depicted in Eiichiro Oda's original manga or the television anime), as well as his reunion with Luffy from his point of view.

The Straw Hat crew salvages a treasure chest from a sinking wreck, inside which they find an old lady. To get the pirates to take her home, she promises them the treasure of a golden crown on her island: Mecha Island. Upon arrival, the crew is attacked by the lord of the island but he has a change of heart and decides to seek their help to solve the mystery of the Golden Crown. (Source: ANN, edited)

According to Weekly Shonen Jump, 3D movies of One Piece and Toriko were announced to premiere on March 19th, 2011. One Piece 3D is an original story about the missing straw hat of Luffy.

Upon hearing news that islands in East Blue are being destroyed, Monkey D. Luffy and his crew go to investigate. On their way, however, an outlandish pirate ship appears out of the sky, helmed by the infamous pirate Shiki the Golden Lion—a man who ate the Float-Float Fruit and the first ever prisoner to escape from Impel Down. In his quest to defeat the World Government, Shiki kidnaps Nami to be his own navigator and sends the rest of the Straw Hat Pirates to his floating islands as hostages, leaving her in a dilemma. Separated in a land under Shiki's absolute control, Luffy and his crew must survive the mystifying terrain in order to bring back their navigator and friend.