He had been folding for a decade. He had mastered the cranes of Yoshizawa, the insects of Lang, the roses of Kawasaki. But Satoshi Kamiya’s Ryujin 3.5 —the Japanese dragon god—was not a model. It was an expedition. A folding Everest.

On the final night, a thunderstorm raged outside. The power flickered. Leo was working on the last detail: the dragon's mane of flame. Kamiya’s diagram called for a “curved, open sink with a locked pleat.” It was a move that wasn't even in the glossary. Leo held his breath. He slipped the tip of his tweezers into a tiny pocket of paper, inverted it, and pulled.

The collapse is the moment in Kamiya's designs where the flat, creased paper, looking like a topographical map of a nightmare, is simultaneously pinched, pushed, and pulled into the 3D silhouette of the creature. It is a form of origami alchemy. Leo took a breath, the scent of rain from the open window mingling with the earthy smell of the paper.

The tail was the worst. It was a narrow, sinuous coil of paper, meant to curl back over the body. One false crimp, and the entire effect was ruined. Leo spent a whole evening on a single inch of the tail, reversing a fold, then reversing it back, until the paper wept microscopic tears.

Leo looked at the crumpled, empty sheet on the floor—the one he had started with. He looked at the dragon.

He leaned back, his back a symphony of aches. On the table lay a lumpy, misshapen bundle of paper, no bigger than a clenched fist. It was ugly. It looked like a crumpled receipt. Anyone else would have thrown it away. But Leo saw the truth: nestled inside that chaos were all 1,376 scales, the segmented spine, the clawed toes, the whiskers.

The Ryujin sat on a black silk cloth. It was not large—maybe seven inches from nose to tail tip. But it was alive. Its scales were a thousand tiny overlapping rhombuses. Its claws gripped the air. Its head was turned slightly, as if sensing an intruder. The paper, once flat and soulless, now had the tension of muscle, the curve of bone.