In a world where loyalty can be stronger than steel and friendships stretch across oceans, One Piece has never shied away from breaking hearts. Oda’s tale of pirates, freedom, and inherited will is filled with epic battles and emotional farewells, but it’s the betrayals that leave the deepest scars.

These are the moments that made fans pause and whisper, “Wait, what?”, twists that didn’t just shake up the story, but redefined it entirely. Some betrayals were carefully planned, others happened in the heat of the moment. But every single one changed the course of arcs, broke character dynamics, and shifted how we saw the world of One Piece itself.

Let’s dive into the most unforgettable backstabbings across the Grand Line, the ones that broke our trust, twisted the plot, and proved that in One Piece, the line between ally and enemy is always razor-thin.

7

Apoo Betrays Kid and Sides with Kaido

The Beat That Dropped Like a Bomb

Before the events of the Onigashima Raid, Eustass Kid, Killer, Basil Hawkins, and Scratchmen Apoo formed what looked like a formidable alliance known as the “Worst Generation’s own Pirate Union.” The plan was to take down a Yonko together, ambitious, reckless, and dangerous, just like the men involved.

But when the crew set foot on Wano, things unraveled fast. Without warning, Apoo turned on Kid and Killer during their approach to Kaido’s stronghold, revealing that he had been working with the Beast Pirates all along.

The betrayal wasn’t just a one-time trick; Apoo had been feeding Kaido information for a long time. The moment Kid and Killer realized this, it was already too late. Kaido dropped from the sky, literally, and crushed their rebellion before it could begin.

What made this betrayal sting wasn’t just the physical damage, it was the audacity of the deception. Apoo smiled through every beat of it. He sent Killer into a downward spiral, leading to his transformation into Kamazo, while Kid ended up in prison alongside Luffy. Apoo, meanwhile, walked freely among Kaido’s elite, spinning tracks and buying time.

In the end, the betrayal was short-lived. Apoo tried to switch sides again during the raid, but no one truly trusted him again, not even the Beast Pirates.

6

Denjiro Disguises as Kyoshiro to Fool Orochi

The Longest Performance on the Wano Stage

Of all the Scabbards, Denjiro played the longest game.

After the death of Oden, Denjiro was a man shattered beyond recognition. His fury twisted his face so much that even his closest comrades wouldn’t have recognized him. That’s when he took on the persona of Kyoshiro, a flamboyant Yakuza boss under Orochi’s payroll.

For two decades, Denjiro lived among his enemies, smiling in banquets and acting loyal to the very people who killed his master. He rose through Orochi’s ranks, becoming the leader of the Kyoshiro family and even the personal bodyguard of Komurasaki, who was secretly Hiyori, the daughter of Oden.

The most chilling part was watching him publicly “strike down” Komurasaki in front of Orochi to protect her secret identity. He played every angle, every lie, and made sure Orochi never suspected a thing.

When the raid on Onigashima began, Denjiro finally dropped the mask. He returned to the Scabbards not as a new ally but as the comrade they had once lost. His betrayal wasn’t of his friends, it was of his enemies. And he pulled it off so perfectly that he might be the only traitor in One Piece fans actually rooted for.

5

York Turns on Vegapunk and the Satellites

The Greediest Star in the Sky

Vegapunk wasn’t supposed to be one person. He was six satellites and one main body, each representing a different part of his brain. York was the “Greed” satellite, her only job was to eat, sleep, and enjoy life while the rest of the minds did the hard thinking.

But as the events of Egghead Island unfolded, it turned out York had outgrown her role. She wanted more than rest and luxury; she wanted power. Specifically, she wanted to become a Celestial Dragon and take Vegapunk’s position as the world’s top scientist.

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York betrayed everyone, her creator, the other satellites, even the Seraphim who served them. She coordinated with the World Government to wipe out the entire lab, setting the stage for a horrifying slaughter.

Her betrayal wasn’t loud. It was slow, methodical, and rooted in a childlike sense of entitlement. She didn’t believe she had done anything wrong. In her mind, she simply wanted to live in luxury, forever.

4

Squard Stabs Whitebeard After Being Tricked

The Wound That Hurt More Than Death

During the Marineford War, there were enemies on the battlefield and then there were the wounds from within.

Squard was a captain under Whitebeard, someone who owed his life and loyalty to the old man. But Akainu saw an opportunity and whispered poison into Squard’s ear, telling him that Whitebeard had secretly made a deal to save Ace while sacrificing the rest of his crew.

Blinded by fear and anger, Squard walked right up to Whitebeard and stabbed him in the chest.

What followed was not retaliation, but mercy. Whitebeard forgave him on the spot and called it the Marines’ fault for turning his own son against him. That moment shifted the tide emotionally, not for victory, but for grief.

Squard’s betrayal didn’t kill Whitebeard, but it shattered the trust within their ranks. It made clear how dangerous words could be, and how even the strongest father figure in the series couldn’t protect his sons from manipulation.

When Whitebeard died later in the war, he didn’t hold a grudge. But fans never forgot that stab.

3

CP9 Outsmarts Galley-La and the Straw Hats

The Cipher Pol That Lived a Lie

Water 7 was supposed to be a mystery story with shipwrights and missing blueprints. Instead, it turned into a story of masks falling, and none more dramatically than the CP9 reveal.

For years, Rob Lucci, Kaku, Kalifa, and Blueno had worked as shipwrights and officials within the Galley-La Company. They were respected, trusted, and celebrated by the people of Water 7. Franky even sparred with them regularly, never once suspecting they were secret agents.

Then, they flipped the script. CP9 revealed their true identities and kidnapped Robin in a calculated move to revive the ancient weapon, Pluton. They didn’t just betray the Straw Hats, they humiliated them. The crew was scattered, their ship destroyed, and Robin taken.

It was a turning point in One Piece. The betrayal lit the fire for the Enies Lobby arc, where Luffy declared war on the World Government. Without this moment, there would be no “I want to live” scene. No Buster Call. No Going Merry farewell.

The betrayal changed the Straw Hats forever. They went from being pirates on an adventure to enemies of a global regime.

2

Pudding Reveals Her Scheme to Break Sanji

The Girl Who Turned Tears Into a Weapon

When Sanji was taken to Whole Cake Island for an arranged marriage, he believed he had finally found someone who truly loved him, Charlotte Pudding, the beautiful daughter of Big Mom.

But everything was a lie.

Pudding was a key player in Big Mom’s plot to assassinate the Vinsmokes. Sweet and charming on the outside, she secretly mocked Sanji, laughing at his earnestness and swooning act. Her third eye and memory-altering Devil Fruit made her both unpredictable and dangerous.

When she revealed her true self just before the wedding, Sanji stood there, smiling through tears. He didn’t retaliate. He just lit a cigarette and accepted it.

And that moment broke her.

Pudding’s betrayal was meant to be cruel, but Sanji’s kindness turned it inward. She started to genuinely fall for him, leading to a strange emotional conflict that made her later regret everything. In the end, she helped the Straw Hats escape, but never told Sanji how she really felt.

1

Kanjuro Betrays the Scabbards from Within

The Ink That Wrote a Tragedy

For years, Kanjuro had fought alongside Kin’emon and the other Scabbards, earning their trust through battle scars and shared grief. He mourned with them, laughed with them, and dreamed of avenging Oden with them.

But when the Raid on Onigashima finally began, Kanjuro dropped his brush and revealed his true colors.

He wasn’t just a traitor, he had been one since day one. A member of the Kurozumi clan, he was Orochi’s spy planted among the Scabbards from the very beginning. Every time a plan failed, every time Orochi somehow knew their moves, it was Kanjuro’s doing.

The betrayal gutted the alliance. Kin’emon, who treated Kanjuro like a brother, was left speechless. The rest of the Scabbards were horrified. And to make it worse, Kanjuro used his ink-based powers to create deadly clones and even kidnap Momonosuke.

It was a betrayal not just of people, but of memory. Kanjuro defiled everything Oden had stood for.

When his end came, it wasn’t noble. It was filled with resentment and delusion. But it made one thing clear: the most dangerous enemy is the one who knows all your secrets.

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One Piece

Release Date

October 20, 1999

Network

Fuji TV

Directors

Hiroaki Miyamoto, Konosuke Uda, Junji Shimizu, Satoshi Itō, Munehisa Sakai, Katsumi Tokoro, Yutaka Nakajima, Yoshihiro Ueda, Kenichi Takeshita, Yoko Ikeda, Ryota Nakamura, Hiroyuki Kakudou, Takahiro Imamura, Toshihiro Maeya, Yûji Endô, Nozomu Shishido, Hidehiko Kadota, Sumio Watanabe, Harume Kosaka, Yasuhiro Tanabe, Yukihiko Nakao, Keisuke Onishi, Junichi Fujise, Hiroyuki Satou