One Piece - Season 4 / Year 2002

Ace fights Smoker while the Straw Hats run for their ship. Luffy reunites with his brother, and together take down agents of Baroque Works.

Ace decides to travel with the Straw Hats, as he is hunting for a man known as Blackbeard. The group arrives first at the 'Green City' of Erumalu only to find it abandoned to the desert. Vivi and Nami explain what Dance Powder is and what it has done to Arabasta.

After leaving Erumalu, the Straw Hats plus Vivi & Ace continue through the desert, facing the many dangers of it.

Nami and Vivi found themselves an easier way to travel in the desert and leave all men behind. While trying to catch up with them, Ace gets lost. Luffy and the rest of the gang find the Desert Pirates, and Vivi meets a figure from her past.

After hearing that a small village has fake Rebel Army bodyguards that have been keeping peace, Vivi asks the men of the crew to test if they are worthy of staying.

Still trekking through the Arabasta desert, the crew beats up a giant desert scorpion for lunch, while Vivi tells Nami about her past and her friendship with Koza.

Ace finds out that Blackbeard is not in Arabasta after all, and leaves the group to continue looking for him. He leaves Luffy a mysterious piece of paper, explaining that it 'will let them meet again.'

Zoro, Chopper and Luffy manage to get themselves lost and stumble across some huge underground ruins.

Baroque Works plan starts to take effect, and for that, the Number Agents gather to meet Mr. 0. Meanwhile, crew finds out that the Rebel Army has moved out of Yuba and headed to Katorea, and the rebel leader Koza is determined to attack.

Vivi and Luffy disagree in how to stop the rebel army and Baroque Works, leading to a fight.

The crew travels to the city of Rainbase to take down Crocodile and Baroque Works, but run afoul of Smoker and Tashigi.

Most of the Straw Hats, along with Smoker, are trapped by Crocodile. Vivi reunites with the royal guardian Pell, but is captured by Miss All-Sunday. Crocodile reveals his invincible Devil Fruit power.

Baroque Works' plan to take over Arabasta is set in motion. The king is kidnapped and framed for a crime, and the rebel army begins to move.

Most of the Straw Hats are helplessly trapped, but Crocodile is contacted by "Mr. Prince".

Chopper distracts Crocodile while Sanji frees the rest of the crew, but find themselves trapped yet again. Smoker's view on Luffy changes a little.

After escaping from Rain Dinners, the Straw Hats and Vivi cross the desert to Alubarne, where the final battle will take place. Crocodile, however, manages to catch Luffy, beginning the first round of their battle.

Luffy is left for dead by Crocodile, but is helped by the mysteríous Miss All-Sunday. Meanwhile, the rest of the Straw Hats reach Alubarna after encountering the Spot-Billed Duck Squad and dangers of Arabasta's main river.

The revolution is on the verge of starting and the crew comes out with a plan that could stop it.

Vivi's attempts to stop the rebel army go to waste, and she is attacked by Mr. 2 Bon Kurei, but manages to escape. Meanwhile, the battle of Usopp and Chopper vs. the Mr. 4 team begins.

Things look hopeless for Usopp & Chopper as they continue to suffer from every attack that the Mr.4 team makes. However, the tides may be beginning to turn as Usopp learns what it truly means to be a man.

Albeit severely beaten and bruised, Usopp and Chopper have finally defeated the Mr.4 team. However, Mr. 2 has figured out Sanji's weakness.

Though Mr. 2 discovers Sanji's weakness, Sanji still defeats his opponent after an evenly-matched fight. Meanwhile, before Vivi could give the word to blow up the palace, Crocodile appears.

Nami faces off against Miss Doublefinger and tries to figure out her new weapon that Usopp made, the Clima-Tact.

While Crocodile reveals to Vivi about the ancient weapon Pluton, Nami attempts to defeat Miss Doublefinger with her most powerful attack: The Tornado Tempo.

While Miss. Doublefinger's fight with Nami was challenging, Zoro is having an even more difficult time fighting Mr.1: A man who can change his entire body into steel - something that Zoro cannot cut. As Zoro nears death, he must discover the secret to "the breath of all things".

When Vivi reveals Crocodile's plan to Koza, he attempts to stop the fighting, but is shot. Crocodile reveals that he has set up a massive bomb in the city.

As Koza tries to stop the Rebel Army, both sides are once more fighting due to the intervention of Baroque Works. Vivi is thrown to her certain death when Luffy saves her and challenges Crocodile to a second round.

Luffy fights Crocodile with more success this time by using water, but still loses this round. Meanwhile, the other Straw Hats hurry to locate the bomb before it goes off. Nico Robin forces the king to take her to the tomb where the Pluton Poneglyph is hidden.

Crocodile joins Robin in the tomb, and orders her to translate the Poneglyph. Robin tells him that Pluton was not mentioned and that it was only about history, but Crocodile figures out that she was lying and stabs her in response. When Luffy recovers from the last round of fighting, he chases after Crocodile into the tomb.

Luffy fights with Crocodile by using blood on his fists. Meanwhile Vivi finds the bomb, and calls the Straw Hats together.

Vivi finds the bomb inside of the clock tower, but the Mr. 7 pair of Baroque Works are there to protect it. Vivi defeats them, but she realizes the bomb cannot be stopped so easily. It has a timer, and right before it blows up, Pell shows up and takes it into the atmosphere, where he sacrifices himself to save Arabasta.

Luffy defeats Crocodile by punching him through solid bedrock. When Crocodile falls, the rain-drops calm the soldiers.

Now that the battle has ended, the outcome is tallied. Igaram appears with proof of Cobra's innocence, as well as Koza telling everything. Tashigi and Smoker both are rewarded for taking on Crocodile, but neither one of them believes that is right, considering the Straw Hat pirates did all the work.

Luffy is rescued from the collapsed tomb where he fought Crocodile and brought into Cobra's palace to rest. When he awakens, a magnificent banquet is thrown for the pirates, then, the Straw Hats are invited to enjoy the hot spring steam room inside the palace.

It's the day for Vivi's speech and her decision whether or not to continue to be with the Straw Hats. Meanwhile, Bon Kurei and his crew attempt to protect the Straw Hats from Hina.

The Marines fail again to catch the Straw Hats. After escaping from Marines, Nico Robin (Ms. All Sunday) appears from inside of Straw Hats ship. She manages to persuade the crew to let her join. Pell is seen at the end standing over his own grave.

After their adventures in Arabasta, the crew come upon another deserted island and split up tasks amongst themselves. Chopper is left in charge of guarding the ship, and he reminisces about the day he first made the rumble ball and his first patient, Dr. Kureha, while spending some time with the newest crewmember: Nico Robin.

A weird salesman is fished out of the water and onto the Going Merry, and Nami buys a ton of "1000 year paper" from him to draw her sea maps. However, that's not going to be easy with the rest of the crew goofing off as usual.

The Going Merry runs into several Marine ships in some fog, and the Straw Hats meet a trainee Marine chef named Tajiyo. Sanji helps him out of a bit of cooking trouble.

The crew stops on an island that's having its annual fireworks festival; Usopp meets a young fireworks-maker named Kodama and helps her achieve her dream.

Zoro has a flashback about the time when he first met Johnny and Yosaku, and faced off against Bandits and, Dick.

After escaping from several Marine ships, the Straw Hats land on an uncharted island and meet an old man named Zenny. Chopper finds out that, because of his bad heart, Zenny probably only has three days to live.

The Straw Hats help Zenny out, hoping to make his last days good ones; they learn about Zenny's past as a money lender, and his dream of becoming a pirate. But Zoro realizes that Zenny has outlived Chopper's predictions and so the straw hats decide that, after helping him finish his pirate ship, they will leave the island.

Zenny decides to follow his dream and become a pirate, despite his age. He helps the Straw Hats out of trouble with the Marines, and then they part ways.