Water 7

A masterpiece of storytelling. The Straw Hats arrive at Water 7, a city of shipwrights, to repair the Going Merry. But they receive devastating news: the Merry is beyond repair and will sink. Usopp, who sees the Merry as a crewmate, refuses to accept this and challenges Luffy to a duel — and leaves the crew. Meanwhile, Robin disappears, seemingly betraying them. The government's secret assassination group CP9, who have been undercover as shipwrights for five years, reveals themselves and takes Robin. Everything falls apart: the crew is broken, their ship is dying, and their friend has been taken by the World Government. It's the lowest point the Straw Hats ever reach.