In Camelot, the castle was in the midst of Christmas celebration, when a lone knight rode into King Arthur's court.

The knight wore clothing that was green. His skin, beard and hair were also green in colour. Even the mane and tail of his horse were green. In the one hand the Green Knight carry a cluster of holly, while in his other hand he carried a great wicked axe.

The Green Knight challenged the famous knights of the Round Table in a game of beheading. The Green Knight wanted one of the knights to use his axe on his own neck; in return the other knight must allow him to cut off the other's head, one day and a year from now. The Green Knight offered his axe as a prize.

No one thought such game was possible without someone being killed. No brave warrior accepted this challenge until the Green Knight had accused Arthur's knights of cowardice. Arthur felt so shamed that none in his knights in court that would have accept the challenge. Arthur would have offered to accept the challenge, until his nephew, Sir Gawain, decided to step forward to accept the Green Knight's challenge.

Gawain agreed to the Green Knight's term, that he would face the blow one-year from now. With this pact sealed, Gawain swung the axe at the Green Knight's neck. Instead of the body collapsing to the floor, the knight bent over and picked up his head.

The Green Knight told the hero to find him at the Green Chapel by the time of Christmas, so Gawain could receive the return blow.

Ten months later, Gawain set out for the Green Chapel. The ladies and damsels grieved for him, since they believed Gawain was going to his death.

His journey north brought him to encounters against wild men and enemy knights. Gawain fought off wolves, ogres and dragons in his travel. The winter winds and snow swirled around him as he treads his way through woods or hills.

Finally on Christmas Eve, Gawain came upon a castle, where Lord Bertilak de Hautdesert and his beautiful wife greeted the travel-weary hero. Bertilak offered the hero lodging, since the Green Chapel was not too far away.

Bertilak told his guest that he would be going on a hunting trip, his wife would entertain the guest during the day. Bertilak told Gawain that they should exchange gifts each day the host returned from hunting. Bertilak would give the hero the gift from his hunt, while Gawain would give to his host anything that the hero would win in his castle.

Early the next morning, when Bertilak went out to hunt, the lord's wife kept Gawain's company. Bertilak chased and hunted deers in the forest.

The beautiful wife flirted with Gawain and set about seducing the hero into sleeping with her. Gawain cleverly and politely turned aside her advances without offending his hostess. Gawain, however, did accept a kiss from his hostess.

In the evening when Bertilak return from the hunt, with all the games he had killed. As they agreed from the previous night, Bertilak gave his kills to Gawain as part of their bargain. Gawain, who had only received a kiss from his host's wife, so Gawain kissed Bertilak upon the lips. Bertilak said it was a fair exchange.

The next day, Bertilak set out again with his huntsmen. This time, Bertilak faced a more dangerous beast in the hunt, the wild boar. The boar had injured some hounds. The arrows used by the bowmen proved to ineffective against he boar's hide. Bertilak chased the wild boar all day. Finally cornering the boar at the river. The boar charged at Bertilak. Both Bertilak and the boar fell in the water. Bertilak killed the boar with his sword.

At the castle, the host's wife continued her attempts to seduce Gawain. Gawain had more difficulties diverting the beautiful lady. The lady tested Gawain' restraint to the limits, because she was one of the fairest in the land. Again he accepted another kiss, before she departed from his bedchamber.

When Bertilak returned to the castle, offering his today's game to Gawain. In return, Gawain kissed his host.

The next day, Bertilak hunt the wily fox that managed to elude the hunters with cunning, before Bertilak managed to kill the fox.

Meanwhile, at Gawain's bed, the game of seduction continued between the lady and the hero. Finally, the hostess gave up all hopes to seduce Gawain.

The lady asked for Gawain's gloves as his token of love to her, while she would give him her ring. The hero refused to accept the ring. Gawain even refused her silk, green girdle, until the knight learned that her belt could protect from harm. The lady claimed that her girdle was a talisman.

Realising the enormity of accepting the challenge from the Green Knight, he could not see how he could escape death from being beheaded. Gawain accepted her gift, and hid the girdle in his clothes. Gawain received another kiss from the fair lady.

When Bertilak returned with the dead fox, he gave the fox to Gawain. Gawain gave his host another kiss, but did not give the girdle to Bertilak.

On New Year Day, Gawain armed himself for the coming encounter with the Green Knight. Bertilak ordered one of his servants to guide Gawain to the Green Chapel.

Outside of the chapel, the hero met the Green Knight. As they had agreed on Christmas Day, last year, Gawain would receive a blow in return from the Green Knight's axe.

When Gawain saw the axe descending towards his neck, he flinched causing the Green Knight to turn aside the blow. The Green Knight berated Gawain, because he did not flinch, when Gawain severed his head from his body. Gawain vowed that he would not flinch again.

The second time the Green Knight brought the axe down on Gawain's neck, he deliberately missed to see if Gawain was true to his promise of not flinching. Gawain became angry at the delay and told him finish this business.

The third time the Green Knight delivered the blow, the Green Knight again deliberately missed the hero's neck, only drawing a little blood from a small nick.

Gawain immediately leaped to his feet, holding his shield in one arm and in his hand he drew his sword. Gawain told the Green Knight he had his chance to strike blow; he offered combat if refusing to play the Green Knight's game.

The Green Knight assured Gawain that the game was truly over. The Green Knight revealed that he was Lord Bertilak de Hautdesert.

The old lady who was attended of Bertilak's wife was actually Morgan le Fay, Arthur's half-sister. It was Morgan who instigated the game, transforming him into the Green Knight. She had hoped that the Green Knight's challenge to a beheading game would frighten Queen Guinevere to death, since Morgan hated the queen.

Bertilak knew about his wife's game to trap Gawain into committing a mortal sin through adultery. The first two blows were feinted, because of the first two days they had fairly exchanged gifts. Gawain's chivalric manners toward his wife were beyond reproach.

On the third day, however, Gawain had failed to give his wife's girdle to him. Since they had agreement on their first night, to exchange gifts each day of whatever they may win. This was only Gawain's only fault, which was why the hero received a nick from Bertilak's axe. Gawain had failed not because he had succumbed to his wife's advance, but because he took the gift from his wife, hoping that the girdle could save his life.

Gawain felt shame for taking the girdle, confessing that he was coward for taking a talisman (girdle). Gawain realised that he had tarnished his reputation. Gawain threw the girdle at Bertilak's feet.

Bertilak comforted the hero that, since he had admitted guilt for his misdemeanour, Gawain had proved that he was still one of the finest knights in the world. Bertilak offered the green girdle as a token of their friendship and as a remembrance of their encounter.

Bertilak again offered hospitality at his castle to Gawain, but Gawain refused. Gawain decided to return to his uncle. Gawain left Bertilak, and headed towards Camelot.

There was great rejoicing at Camelot, when they found that Gawain had survived his ordeal. Arthur and Guinevere asked the knight of his adventure. Gawain faithfully told them of his shame at Bertilak's castle and the Green Chapel. Gawain told them that he was not worthy of their attention. Gawain now worn the green girdle as a badge to marked his cowardice, his shame and his broken promise to his host.

The king and his companion at the Round Table thought differently on his splendid exploit. Arthur asked the other knights to wear a similar badge.