Chapter 606: Deep Sea Adventure

The crew left aboard the Sunny searches the lightless water for Luffy, Zoro, and Sanji, but even the headlights fail to cut far through the dark. A swarm of giant jellyfish surrounds them, and Robin stops Chopper before he can touch a poisonous tentacle. Franky fires a Coup de Burst to escape a Sea King, after which Brook spots that Caribou has slipped his ropes. The stowaway is actually hiding inside a nearby barrel, plotting to strike once they land, until Franky finds him and bolts the barrel shut. Franky deduces that Caribou let Sanji hit him earlier to mask his mud-based Logia abilities.

Rising heat warns the crew they have drifted over a field of deep-sea volcanoes, and Franky steers clear before any erupt. After a chase by tube-worms and other creatures, a distant glow turns out to be an enormous angler fish. A towering humanoid the crew identifies as a sea giant, later named Wadatsumi, strikes the fish for breaking its captain's rules. Brook then hears singing as a weathered, ancient vessel emerges from the gloom.

Brook names it the genuine Flying Dutchman and recounts its tale: centuries ago a captain went mad and hurled his own crew overboard, drawing divine punishment that doomed him to sail forever without ever reaching port. The shadowed figure aboard, Vander Decken, orders Wadatsumi and the angler to wreck the Sunny for treasure. Out of fuel, the crew is rescued when the kraken bursts in and knocks Wadatsumi out. Luffy, Zoro, and Sanji, all crammed into one bubble, reappear alive, and Luffy reveals he has tamed the kraken and named it Surume, just as a volcano begins to rumble.

Robin shows concern for a crewmate's safety for the first time by stopping Chopper from touching a jellyfish. Franky reveals tools stored in his forearms and seals Caribou inside a barrel despite the stowaway's Logia power. Caribou's Devil Fruit is confirmed to be mud-based. An undersea giant called Wadatsumi makes his debut. The backstory of the cursed Flying Dutchman and its captain, Vander Decken, comes to light. The kraken is shown to be tamed and christened Surume by Luffy. He, Zoro, and Sanji rejoin their crewmates after being separated.

This marks the first time Robin worries aloud for another crew member rather than describing a grim way they might die. Franky demonstrates that his forearms hold an assortment of equipment. The introduction of Wadatsumi and the reveal of the Flying Dutchman's legend set up the antagonists tied to Fish-Man Island. Caribou keeps his cover blown only because he chose not to fight back, which Franky notes spared the crew real trouble.