It happened at this time that Queen Guenever was thrown into great peril of her life. A certain squire who was in her immediate service, having some cause of animosity to Sir Gawain, determined to destroy him by poison, at a public entertainment. For this purpose he concealed the poison in an apple of fine appearance, which he placed on the top of several others, and put the dish before the queen, hoping that, as Sir Gawain was the knight of greatest dignity, she would present the apple to him. But it happened that a Scottish knight of high distinction, who arrived on that day, was seated next to the queen, and to him as a stranger she presented the apple, which he had no sooner eaten than he was seized with dreadful pain, and fell senseless. The whole court was, of course, thrown into confusion; the knights rose from table, darting looks of indignation at the wretched queen, whose tears and protestations were unable to remove their suspicions. In spite of all that could be done the knight died, and nothing remained but to order a magnificent funeral and monument for him, which was done.
Some time after Sir Mador, brother of the murdered knight, arrived at Arthur's court in quest of him. While hunting in the forest he by chance came to the spot where the monument was erected, read the inscription, and returned to court determined on immediate and signal vengeance. He rode into the hall, loudly accused the queen of treason, and insisted on her being given up for punishment, unless she should find by a certain day a knight hardy enough to risk his life in support of her innocence. Arthur, powerful as he was, did not dare to deny the appeal, but was compelled with a heavy heart to accept it, and Mador sternly took his departure, leaving the royal couple plunged in terror and anxiety.
During all this time Launcelot was absent, and no one knew where he was. He fled in anger from his fair mistress, upon being reproached by her with his passion for the Lady of Shalott, which she had hastily inferred from his wearing her scarf at the tournament. He took up his abode with a hermit in the forest, and resolved to think no more of the cruel beauty, whose conduct he thought must flow from a wish to get rid of him. Yet calm reflection had somewhat cooled his indignation, and he had begun to wish, though hardly able to hope, for a reconciliation when the news of Sir Mador's challenge fortunately reached his ears. The intelligence revived his spirits, and he began to prepare with the utmost cheerfulness for a contest which, if successful, would insure him at once the affection of his mistress and the gratitude of his sovereign.
The sad fate of the Lady of Shalott had ere this completely acquitted Launcelot in the queen's mind of all suspicion of his fidelity, and she lamented most grievously her foolish quarrel with him, which now, at her time of need, deprived her of her most efficient champion.
As the day appointed by Sir Mador was fast approaching, it became necessary that she should procure a champion for her defence; and she successively adjured Sir Hector, Sir Lionel, Sir Bohort, and Sir Gawain to undertake the battle. She fell on her knees before them, called heaven to witness her innocence of the crime alleged against her, but was sternly answered by all that they could not fight to maintain the innocence of one whose act, and the fatal consequence of it, they had seen with their own eyes. She retired, therefore, dejected and disconsolate; but the sight of the fatal pile on which, if guilty, she was doomed to be burned, exciting her to fresh effort, she again repaired to Sir Bohort, threw herself at his feet, and piteously calling on him for mercy, fell into a swoon. The brave knight was not proof against this. He raised her up, and hastily promised that he would undertake her cause, if no other or better champion should present himself. He then summoned his friends, and told them his resolution; and as a mortal combat with Sir Mador was a most fearful enterprise, they agreed to accompany him in the morning to the hermitage in the forest, where he proposed to receive absolution from the hermit, and to make his peace with Heaven before he entered the lists. As they approached the hermitage, they espied a knight riding in the forest, whom they at once recognized as Sir Launcelot. Overjoyed at the meeting, they quickly, in answer to his questions, confirmed the news of the queen's imminent danger, and received his instructions to return to court, to comfort her as well as they could, but to say nothing of his intention of undertaking her defence, which he meant to do in tne character of an unknown adventurer.
On their return to the castle they found that mass was finished, and had scarcely time to speak to the queen before they were summoned into the hall to dinner. A general gloom was spread over the countenances of all the guests. Arthur himself was unable to conceal his dejection, and the wretched Guenever, motionless and bathed in tears, sat in trembling expectation of Sir Mador's appearance. Nor was it long ere he stalked into the hall, and with a voice of thunder, rendered more impressive by the general silence, demanded instant justice on the guilty party. Arthur replied with dignity, that little of the day was yet spent, and that perhaps a champion might yet be found capable of satisfying his thirst for battle. Sir Bohort now rose from table, and shortly returning in complete armor, resumed his place, after receiving the embraces and thanks of the king, who now began to resume some degree of confidence. Sir Mador, growing impatient, again repeated his denunciations of vengeance, and insisted that the combat should no longer be postponed.
In the height of the debate there came riding into the hall a knight mounted on a black steed, and clad in black armor, with his visor down, and lance in hand. "Sir," said the king, "is it your will to alight and partake of our cheer?" "Nay, sir," he replied; "I come to save a lady's life. The queen hath ill bestowed her favors, and honored many a knight, that in her hour of need she should have none to take her part. Thou that darest accuse her of treachery, stand forth, for to-day shalt thou need all thy might."
Sir Mador, though surprised, was not appalled by the stern challenge and formidable appearance of his antagonist, but prepared for the encounter. At the first shock both were unhorsed. They then drew their swords, and commenced a combat which lasted from noon till evening, when Sir Mador, whose strength began to fail, was felled to the ground by Launcelot, and compelled to sue for mercy. The victor, whose arm was already raised to terminate the life of his opponent, instantly dropped his sword, courteously lifted up the fainting Sir Mador, frankly confessing that he had never before encountered so formidable an enemy. The other, with similar courtesy, solemnly renounced all further projects of vengeance for his brother's death; and the two knights, now become fast friends, embraced each other with the greatest cordiality. In the meantime Arthur, having recognized Sir Launcelot, whose helmet was now unlaced, rushed down into the lists, followed by all his knights, to welcome and thank his deliverer. Guenever swooned with joy, and the place of combat suddenly exhibited a scene of the most tumultuous delight.
The general satisfaction was still further increased by the discovery of the real culprit. Having accidentally incurred some suspicion, he confessed his crime, and was publicly punished in the presence of Sir Mador.
The court now returned to the castle, which, with the title of "La Joyeuse Garde" bestowed upon it in memory of the happy event, was conferred on Sir Launcelot by Arthur, as a memorial of his gratitude.