It was New Year's Eve at Camelot. The great hall was decked with green branches and red berries, and King Arthur, Queen Guinevere, and all the Knights of the Round Table were gathered for a magnificent feast. There was music, laughter, and joy on every side, for it was the most important celebration of the year.

Arthur had a tradition: on New Year's Day he would not eat until something marvelous had happened — an extraordinary adventure, an incredible tale, or a challenge worthy of his knights. Everyone was waiting to see what wonder would come that year.

Suddenly, the great doors of the hall burst open with a crash.

In rode the strangest figure anyone had ever seen. He was an enormous knight on a giant horse, and everything about him was green. His skin was green as grass, his hair green as leaves, his clothes emerald green. Even his horse was green as moss, and his armor gleamed in a thousand shades of green. In his hands he carried two things: a huge axe, and a branch of holly.

The hall fell utterly silent. Everyone stared open-mouthed as the Green Knight rode to the center of the hall. Then he spoke, in a voice like thunder:

"Where is the captain of this company? I have a game to propose. Which knight of Camelot is brave enough to accept my challenge?"

Arthur rose to his feet.

"I am Arthur, king of this land. You are welcome at Camelot. What game do you propose?"

The Green Knight laughed, a deep and eerie laugh.

"A simple game. Anyone here may strike me one blow with this axe. A single blow, as hard as he likes."

The knights glanced at one another. That sounded far too easy.

"But there is a condition," the Green Knight went on, with a dark smile. "A year and a day from now, the one who strikes me must come and find me at my Green Chapel. There, I will give him a blow just like the one he gave me."

Now the knights understood. Whoever struck the Green Knight would have to take a blow in return, one year later. No one moved, and no one spoke.

Arthur flushed red with anger to see his knights standing there like cowards. He took up the axe himself.

"If no one accepts, then I will."

But before Arthur could act, a young knight stood up.

"My king," said the young man, "allow me to accept this challenge. I am the weakest and least wise of these knights; if I fail, the loss will be small. But you, my king, are far too precious to risk."

It was Sir Gawain, Arthur's nephew and one of the noblest knights of the Round Table. Arthur hesitated, but he saw the determination in his nephew's eyes.

"So be it, then. The challenge is yours, Sir Gawain."

Gawain took the giant axe. The Green Knight dismounted, knelt, and bent his head, baring his neck.

"Strike your blow, Sir Gawain. Do not be afraid."

Gawain raised the axe in the air and took a deep breath. Then, with all his strength, he struck. The Green Knight's head flew through the air and rolled across the floor. Everyone waited for the body to fall down dead. But it did not fall.

The headless body stood up. It walked quite calmly to where the head had rolled, picked it up by the hair, and lifted it high. The head's eyes opened, and its mouth spoke:

"Well struck, Sir Gawain. Now remember your oath. A year and a day from now, come and find me at the Green Chapel, and there you will receive the blow you gave me. Do not fail, or you will be called a coward forever."

The Green Knight mounted his horse, still holding his own head, rode out of the hall, and the doors closed behind him. The silence was absolute. What had they just witnessed?

Gawain looked at the axe in his hands. He had sworn an oath: in a year's time, he would have to find the Green Knight and take an axe-blow on his neck.

"This axe shall hang above the Round Table," Arthur ordered, "to remind everyone of Sir Gawain's oath."

The year passed quickly. Summer came, then autumn, then winter, and Gawain lived as he always had, fighting and being a good knight. But he never forgot his promise. When autumn came round again, he knew it was time to go.

On All Saints' Day, he put on his finest armor. On his shield was a golden five-pointed star, the sign of his five virtues: generosity, brotherhood, purity, courtesy, and compassion.

Arthur and all the knights were sorrowful, for they believed Gawain was riding to his death. How could anyone survive an axe-blow to the neck? But Gawain was brave.

"I gave my word. A knight does not break his word."

He mounted his horse and set out in search of the Green Chapel.

Gawain journeyed through many desolate lands. He fought wolves, bears, and bandits, shivered in the mountains and sweltered in the valleys, and no one could tell him where the Green Chapel was. On Christmas Eve, when he was close to giving up, he caught sight of a beautiful castle in the middle of a forest.

He knocked at the gates and was welcomed by the lord of the castle, a big, cheerful, hospitable man with a red beard.

"Welcome, Sir Gawain. Stay with us for Christmas. The Green Chapel is near here; you can ride there on the appointed day."

Gawain, relieved and grateful, spent Christmas at the castle. And the lord proposed a game:

"I am going out hunting for three days. Whatever I catch, I will give to you. And whatever you win here in the castle, you will give to me. Do you agree?"

Gawain agreed. It seemed a harmless game.

Over the next three days, strange things happened. The lord went out hunting, and Gawain stayed resting in the castle. But the lord's wife came to visit him, and tried to charm him with sweet words and fine gifts.

Gawain found himself in a difficult dilemma. She was beautiful and kind, but he was an honorable knight, and he could not betray his host's hospitality. On the first day she gave him one kiss, and that evening, as part of the game, Gawain gave one kiss to the lord. On the second day it was two kisses, and Gawain returned both. On the third day, three kisses... and a magic green girdle.

"This girdle will protect you from any wound," she said. "Wear it when you meet the Green Knight."

Gawain accepted the girdle. That evening he gave the lord the three kisses, but he said nothing about the girdle. For the first time, Gawain had broken his word. He had hidden something.

On the appointed day, Gawain rode to the Green Chapel. He found a grim place, a green-covered hollow beside a stream. And there he was: the Green Knight, sharpening his axe.

"Ah, Sir Gawain, you came. You kept your word. Now kneel and receive your blow."

Gawain knelt and bared his neck. His heart was pounding, but he would not run. The Green Knight raised the axe, and Gawain heard the blade whistle through the air. He could not help it: he flinched. The axe stopped inches from his neck.

"Well now," mocked the Green Knight. "Do the knights of Camelot tremble?"

"Strike again," said Gawain, resolute. "I will not move."

The Green Knight lifted the axe once more. This time, Gawain did not move. The axe came down... and stopped again.

"Once more," said the Green Knight, smiling.

A third time he raised the axe, and this time he truly struck. But the blade only grazed Gawain's neck, a small cut that barely bled.

Gawain sprang to his feet, relieved.

"I have taken my blow, and my honor is satisfied. If you strike again, I will defend myself!"

The Green Knight laughed aloud.

"There is no need. Your test is over."

Then something astonishing happened. The knight's green skin faded away, and there stood the lord of the castle, the man with the red beard.

"I am the lord of the castle, Sir Gawain. I was turned into the Green Knight by magic, to put the knights of Camelot to the test."

"The three blows were tests," he explained. "Twice you were perfectly honest and gave back the kisses; so twice I spared you. But on the third day you hid the green girdle. Hence the small cut on your neck: the mark of your small dishonesty."

Gawain was ashamed. He had failed; he had hidden the girdle out of fear.

"Forgive me," said Gawain. "I was a coward. I kept the girdle because I was afraid to die."

"You are human," said the knight. "And you are honest about your fault; that too is honor. Keep the green girdle as a reminder: perfection is impossible, but we must always strive to be better."

Gawain returned to Camelot wearing the green girdle over his armor, as a reminder of humility, and he told the whole story. The knights embraced him and said that any of them would have failed worse, and that being honest about one's own fault was true nobility. And from that day on, all the Knights of the Round Table wore a green sash, to remember that they were human, not perfect — but must always seek honor and truth.