It was a time when pirates ruled the seas. Several bands of pirates were battling over the great hidden treasure, One Piece, which was left by the now legendary pirate captain, Gold Roger. There was a young boy who admired the pirates, his name was Monkey D. Luffy. One day, he mistakenly eats the devil's fruit and turns himself into a rubber human being.
Ten years have passed since that incident. Luffy sets out to sail all alone. He sets out to become a great pirate captain and that's when his great adventure begins. "I'm going to be the Pirate King! I'm going to get One Piece!".
The crew arrives at the last large town before the entrance to the Grand Line--Loguetown, the place where Gold Roger was both born and executed, where they stock up on supplies and sightsee. As Luffy heads for the execution platform where Roger was killed, old enemies are searching for him.
While searching for new swords to replace the ones shattered by Mihawk, Zoro meets a woman named Tashigi, who looks exactly like an older Kuina, who then helps him look.
(filler) Usopp manages to anger the daughter of bounty hunter Daddy the Father, and finds his own life at stake. When Daddy discovers that Usopp is the son of Yasopp, the only man to beat him, he challenges him to a duel.
(filler) In order to win a rare fish, Sanji enters a cooking contest and faces a woman named Carmen.
Luffy arrives at the execution platform only to be caught in a trap by Buggy and Alvida.
Miraculously saved from death by an unnatural green fog and a lightning bolt to Buggy, the Straw Hats rush out of Loguetown, only for Zoro to be stopped by Tashigi and Luffy to be stopped by Captain Smoker.
On a stormy night a girl called Apis escapes from the Marines and arrives at Straw hat's ship, but the girl upon knowing that they are pirates begins to hide some of the reasons which she is being wanted by the Marines. As the Straw Hats escape from the Marines, they get caught in the Calm Belt.
The Calm Belt is revealed to have no winds or currents as well as being the home of many giant sea kings. Apis forms a plan with Luffy's help and escapes the sea kings by riding with one's sneeze. Later, the crew reaches Battleship Island, where they listen to the soporific story of the island's creation. After following Apis into a cave where a dragon is hidden, Luffy and Nami find the reason why Apis is being chased.
Now that the crew is informed about the reasons for which Apis was followed, they hurry to escape the island so Ryuuji could be saved, but they meet with a foe that wants Ryuuji to himself. Zoro and Usopp bring the ship to a thin rock at the side while Nami and Api get Ryuuji onto a cart. Luffy and Sanji fight the Marines to buy time for all preparations. In the end, the ship pulls the cart away on the search for Lost Island.
After arriving to what might seemed as the Lost Island the Straw hats where looking for, they find an old Temple with paintings that might indicate where the Lost Island really is, and also Erik who has been following them throughout the sea.
Zoro is left fighting with Erik while Luffy and the gang run to the ship in order to get to Lost Island, but only find more problems.
At last Admiral Nelson has seen through the ambitions of Erik, but takes it a little too personally and now the mystical dragon's life is in danger.
With his last breath, Ryuuji calls all his fellow dragons, and the Lost Island re-surfaced. Meanwhile Luffy takes out Admiral Nelson and his gang.