Episode 1090 begins with the Thousand Sunny in danger, nearly swallowed by a giant red cyborg shark. Jinbei, demonstrating his speed and agility, just manages to free the ship from the shark's grasp. Meanwhile, Luffy, Chopper, and Bonney fall into the sea, prompting Jinbei to order Franky to take control of the ship while he rescues them. Franky activates a hidden propeller drive beneath the ship to escape the relentless shark, which attacks the ship with torpedoes. The explosion sends the ship flying into the air, capsizing it and causing it to sink, with the crew being thrown into the water.

Meanwhile, Jinbei succeeds in rescuing Luffy, Chopper, and Bonney from the sea. As they surface, they encounter the shark again, which now fires cannonballs. Jinbei, recognizing the imminent danger, dives back underwater with the others but is hit by the shockwave of the exploding cannonball.

Back on the Thousand Sunny, now submerged, Franky struggles to regain control amid the strong currents. The situation escalates when the shark returns to devour the ship, only to be thwarted by the sudden appearance of a giant blue robot that drives the sea monster away.

The episode then shifts to Marine Base G-14, where Tashigi and her team administer medicine to Mocha and the other children from Punk Hazard. This medicine is meant to reverse the effects of Caesar's giant growth experiment. Vice Admiral Doll interrupts the conversation, expressing her frustration with Helmeppo, who is preoccupied with the kidnapping of his best friend Koby by Blackbeard. In a separate room, Helmeppo and Hibari ask Rear Admiral Prince Grus for help in rescuing Koby, pointing out the danger of attacking Blackbeard's fortress, Hachinosu, also known as Beehive. Helmeppo suggests using Seraphim from Egghead for the mission, but Grus hesitates due to his lack of contact with Drake.

The scene then shifts to Egghead, where Jinbei has brought Luffy, Chopper, and Bonney to a cave on the shore. As they dry their clothes, Bonney introduces herself to Luffy and tells him that she wants to meet Dr. Vegapunk on Egghead after leaving her team elsewhere.

The episode ends with a major surprise aboard the Thousand Sunny. As the crew regains consciousness, they realize that the blue robot has rescued their ship from the sea. Franky and Usopp express their admiration for the robot, while Robin wonders about its controls. A young woman emerges from the robot and introduces herself as Dr. Vegapunk, a scientist working for the World Government.