!! Short Summary
A filler arc that takes place after the ''[[Recap/OnePieceSkypieaArc Skypiea Arc]]''. The Straw Hats accidentally float down into the Marine base, G-8, after their adventure in Skypiea. Forced to abandon ship, the crew must make their way through the base to reclaim the Going Merry and avoid capture. But it's not gonna be easy as the captain of the base, Jonathan, is a protege of one of the Marine Admirals, Akainu, and able to track their every move.

!! Main Summary

''G-8'' arc has the following tropes:

* AchievementsInIgnorance: Zoro managed to get the crew lost ''in a straight hallway'' and thus avoided the ambush the Marines had set for them.
* AintTooProudToBeg: A variant, during the group's time undercover in the base. Sanji meets Jessica, the head chef, and shows her a recipe for a tasty dish. But when he's revealed as a pirate and later escapes, Jessica tries to throw the recipe away. Her whole staff beg her to swallow her pride and let them use it since they like his cooking. Jessica grudgingly agrees and they use the recipe.
* AntiVillain: Jonathan only wants to defend his base from invaders (and of course perform his duty as a marine to capture wanted pirates), and proves to be a very amiable person who treats the Straw Hats as [[WorthyOpponent Worthy Opponents.]]
* ArsonMurderAndJaywalking:
-->'''Shepherd''': I've been subjected to humiliation, and incarceration, and being called "Condoriano"!
* BigNo: Usopp's response when he realizes that he's the one who's going to have to fire the Impact Dial (which really hurts the user) in order for the Straw Hats to escape.
* ButtMonkey / HumiliationConga: Poor Shepherd.
* CameFromTheSky: The Going Merry had fallen from the sky and into the heavily guarded Marine base, leaving the Marines wondering how the Straw Hats managed to infiltrate them. When interrogated, Zoro [[SarcasticConfession honestly told them]] that they'd come from the sky.
** This even doubles as a BrickJoke as Mekao had seen this happen and told some of the Marines, [[CassandraTruth but wasn't believed]]. When the Straw Hats manage to escape via the octopus balloon and take off into the air, essentially leaving the way they came in, he promptly tells them "IToldYouSo".
* TheCameo: Commander Jonathan shows up later in the Marineford Arc.
* ChekhovsGun: The octopus balloon they received from Skypiea.
* ContinuityNod: To the movies oddly enough. Drake comments he's actually ran into the Straw Hats twice when the base identify their ship. And indeed he has, the first time during the ''Anime/DeadEndAdventure'' movie and the second during the ''Anime/TheCursedHolySword'' film.
* TheChessmaster: Jonathan is quite good at coming up with strategies, even some on the fly.
* DelayedReaction[=/=]DoubleTake: The rest of the Straw Hats after Luffy reveals that he still has the octopus balloon.
-->'''Luffy''': I have it.\\
'''Everyone''': "He has it." "He says he's got it." "He has it?" "He's got it."\\
'''Luffy''': Yup, sure do.\\
'''Everyone else except Robin''': [[BigWhat WHAT?!]] Where?
* DressingAsTheEnemy: All of the Straw Hats except for Zoro do this at some point during the arc, in order to blend in: Luffy and Sanji as cooks, Nami as a janitor and later a nurse, Chopper as a doctor, Usopp as a Marine grunt, and Robin as Inspector Shepherd.
* EpicFail: ''Every'' time Shepherd tries to use his high-tech bazooka gun. The first time, he shoots it ''backwards'', into a crowd of Marines. Then, Robin uses her powers to make him repeatedly shoot it in the wrong direction. Later, when he tries to shoot the Straw Hats and the ''Merry'' with it when they make their escape, he misses and accidentally takes out ''the very cannon that was about to shoot them down''.
* FacePalm: Jonathan does this after Shepherd unleashes a cannon on the base ''itself'' in an effort to destroy the Straw Hats.
* {{Foreshadowing}}: Usopp is told by a kindly engineer that the Merry has gotten too many dings during its journey and needs a proper shipwright. During a regroup in one of the unused ports, the crew agree the money they gained should be used in repairing the ship and that they need a shipwright.
** Said engineer, Mekao, also seemed to know about the [[spoiler: Klabautermann, which foreshadowed the Going Merry's death]]. He is pulled away before revealing this, however, in order for Franky to give Usopp this information later.
** Whether or not this was intentional, this was the first mention of the G bases the World Government uses, as it involves Marines who have pride of their base and different personalities, and a Vice Admiral to lead said base. [[spoiler: In the Punk Hazard Arc after the TimeSkip, that same format fits the G5 base, with Vice Admiral Smoker in charge.]]
* GlowingEyesOfDoom: PlayedForLaughs; the rest of the Straw Hats get these in response to Usopp wondering who should fire the Impact Dial. (Of course, they pick him).
* HappilyMarried: Jonathan, the base commander, and Jessica, the head cook.
* HotBlooded: The Hot Wind Marine corps.
* IdentityAmnesia: Usopp invokes this on Shepherd, who Robin was impersonating at the time and the guards had mistaken him for one of the Straw Hats. Usopp plays this out by acting shocked that his friend "Condoriano" cannot recognize him and must have hit his head, hence why he kept claiming he was someone he wasn't.
* IndyPloy: The Straw Hats make use of several of these throughout the first half of the arc when they're trying to avoid being caught by the Marines. Most of these plots involve disguise and infiltration.
** When Usopp realizes that the Marines think the real Shepherd is one of them (since Robin is currently pretending to be Shepherd), he successfully manages to convince the Marines that Shepherd is their comrade "Condoriano", with Zoro helping the ruse.
** When the Straw Hats are attempting to make their escape on the ''Going Merry'', they are surrounded by about a gazillion men with guns and swords. Dr. Kobato, and Nami soon after, pretend to be Chopper's hostages in order to help the crew get to the deck safely. The others quickly play along (with [[IdiotHero Luffy even thinking that Chopper's being serious]]).
* LeaningOnTheFourthWall: At the end of the first episode of the arc when Johnathan comments on how the Straw Hats will be able to escape the base, he's looking directly at the camera (i.e: the viewer) when he says it.
* LetsGetDangerous: A downplayed and subtle example with Luffy, but it's there. During the first confrontation between Luffy and Jonathan in the latter's office, Luffy spends most of it grinning and cheerfully munching on Jonathan's food, entirely unconcerned as usual about being found out. However, once Jonathan informs Luffy that [[NumberTwo Zoro]] was captured, Luffy ''immediately'' stops laughing and becomes deadly serious, gets his [[TranquilFury dangerous blank expression]] on, and prepares to fight Jonathan (towards whom, until then, he'd been quite amiable).
* NiceJobFixingItVillain: Shepherd, whose attempts to capture the Straw Hats himself only ends up aiding them.
* OhCrap: Usopp's reaction when, after he wonders aloud who should be the one to fire the Impact Dial, the rest of the Straw Hats give him evil grins and GlowingEyesOfDoom before unanimously deciding that Usopp ''himself'' should be the one to do so. His response is a BigNo.
* SarcasticConfession: When a captured Zoro is being interrogated by the Marines on how he managed to sneak into their well-defended fortress, he tells them that his ship had fallen from the sky.
* SoundOff: The Hot Wind Marines sing one even when engaging the enemy.
-->''We are Navarone's combat corps!~''
-->''Let them feel the hot wind of our souls!~''
* StormingTheCastle: Luffy and Sanji do a mild version when they charge into the brig (despite knowing that there's a giant squadron of Marines waiting for them) to rescue Zoro and Usopp.
* SupremeChef: The Navarone cooks are REALLY good at what they do, but Sanji takes the cake here. He prepares a meal to put a kitchen full of professional cooks to shame...using the ingredients said cooks ''threw away''
* {{Troll}}: Luffy messes with one Marine for the fun of it. Usopp also had some fun messing with Shepherd, as seen above.
* TheUnfought: Despite being the "BigBad" of the arc, Luffy never really fights with Jonathan. In fact, the main struggle is overcoming his traps to get out of the base.
* UseYourHead: Zoro knocks "Condoriano" (Shepherd) unconscious this way (to keep him from spoiling Usopp's ruse), since he was handcuffed at the time.
* WoundedGazelleGambit: Nami while dressed as a nurse pretends that the "invading pirates" had attacked her and threw off suspicion from her.
* YourPrincessIsInAnotherCastle: Just as the Straw Hats are about to escape the fortress thanks to Luffy blowing a hole in the gate, Nami realizes that all their treasure from Skypeia is gone, so they have to go back for it.