The man picked up both oyster and key, and sure enough, there was a tiny keyhole in the oyster shell, on the opposite side from the hinge. He fitted the key into the lock and turned it, and the shell began to open. He worked it farther open with his knife. As he did so the oyster died, as oysters will when their shells are opened. Inside the oyster, in the place where a pearl might have been, was another golden key, slightly larger than the first one.

The man ate the oyster and took the key and went on his way. Soon he arrived at a house in a forest, and he knocked on the door to see if the owners could give him shelter for the night. The door was slightly ajar, so he pushed his way inside. He found the house full of beds, every room was crammed with them, and in each bed a man or a woman was sleeping. He strolled through the house until he finally found an empty one for himself. There was a clock on the wall that had run down. There was no key to wind it with, so he used the key he found in the oyster’s shell. Then he went to bed.

In the morning the clock struck seven, and he awoke. So did the other sleepers in the house. Each of them repeated the same story: they’d come to the house as strangers and taken beds for the night, but they appeared to have slept for years and years, in some cases centuries, right up until the clock struck. As the man packed up his things he found a golden key under his pillow, slightly larger than the one he had used to wind the clock.

It grew colder as the man walked. Perhaps it was colder everywhere since his daughter had been put in the castle. In time the man met a beautiful woman sitting in a pavilion, weeping because her harp was out of tune. He gave her the golden key to tune her harp, and she gave him a larger one in exchange. That one turned out to be the key to a chest buried under a tree root, with yet another, still larger key inside, which let him into a castle—but not the castle with his daughter in it—with a key resting on a table in the highest room of the tallest tower.

The man walked and walked, for weeks or months or years, he couldn’t tell anymore. When he couldn’t walk anymore he sailed, and when he couldn’t sail anymore he was at the End of the World, where sat a dignified man in a dinner suit, dangling his long legs over the edge. He was patting his lapels and turning out his pockets and looking generally perplexed.