Episode 604

"Get to Building R! The Pirate Alliance's Great Advance!" is the 604th episode of the One Piece anime.

Short Summary
Although the Straw Hat Pirates and Brownbeard were able to successfully make it inside the laboratory, they left a large gaping hole in the side of it, allowing the Shinokuni gas to flow in freely. This prompts the G-5 to frantically seal up the hole as the Shinokuni continues to spread throughout the island.

The G-5 marines then turn their guns and swords towards the Straw Hats, preparing to arrest them. Suddenly, Law appears to tlel them that the only safe route off the island is in a passage called R-66 found only in Room R. The marines are initially reluctant, but quickly change their mind when Smoker repeats the order to them. Smoker then orders Tashigi to take command of the men and rescue the children as he goes off to face Vergo. Prior to Luffy going off to fight Caesar again, Zoro calls out to Luffy reminding that this is the beginning of the New World and musn't let his guard down again, and Luffy happily complies as he plows through the Satyr soldiers.

Caesar Clown then receives the news that the Straw Hats and Marines have broken into the Lab, leaving him alarmed and flabbergasted at their escape.

Long Summary
Though the Straw Hat Pirates and Brownbeard (along with the dragon) managed to escape into the lab, they left behind a gaping hole. But they soon realize that Shinokuni can now enter the lab. The G-5 marines panickly seals the hole back up with various wooden and metal planks. They succeeded in sealing the hole as Shinokuni proceeds to spread throughout the island. Brook uses the power of his Devil Fruit to become a soul and survey the area outside of the lab, noting that "it was like the land of the dead" and "one step outside would kill you".

After regaining their senses, the G-5 marines then turn their guns and swords towards the Straw Hats preparing to arrest them. Nami notices Law and demands him to switch back her's and Sanji's body, to which Sanji secretly refuses. Law agrees to return them to their original bodies and uses Shambles to switch their hearts back. Nami notices that she was wearing a different coat and punches Sanji, accusing him for peeping at her body. Law then explains to everyone present that they only have two hours to escape, he then continues by saying the only passage that leads safely out of the island is called R-66 and is found in Room R. The Marines were reluctant, but quickly changes their mind when Smoker repeated the order to them. Smoker then orders Tashigi to take command of the men and rescue the children as he goes to confront Vergo.

Meanwhile, Caesar Clown is celebrating the deaths of his victims but notices that the cage has no solidified bodies, which he needed to prove the power of Shinokuni. He also notices the absence of the G-5 Marines outside of the lab. Vergo concludes that Luffy and the others must have broken out of the cage and helped the G-5 soldiers escape.

Before Luffy went to fight Caesar again, Zoro calls out to Luffy reminding him that this is just the beginning of the New World and he mustn't let his guard down again, and Luffy happily complies as he plows through the Satyr soldiers using Gomu Gomu no UFO. Caesar Clown then receives the news that the Straw Hats and Marines have broken into the Lab, leaving him alarmed and flabbergasted at their escape.

Anime Notes

 * In the manga, Law simply tells everyone to find the gate marked "R-66" while in the anime, Law explains the layout of the facility.
 * The anime adds a scene in which Luffy asks Robin for a favor.