So then they sailed till by fortune they came nigh a castle that hight Pluere, and thereby arrived for to repose them, weening to them to have had good harbourage. But anon as Sir Tristram was within the castle they were taken prisoners; for the custom of the castle was such; who that rode by that castle and brought any lady, he must needs fight with the lord, that hight Breunor. And if it were so that Breunor won the field, then should the knight stranger and his lady be put to death, what that ever they were; and if it were so that the strange knight won the field of Sir Breunor, then should he die and his lady both. This custom was used many winters, for it was called the Castle Pluere, that is to say the Weeping Castle. CHAPTER XXV. How Sir Tristram and Isoud were in prison, and how he fought for her beauty, and smote off another lady’s head. Thus as Sir Tristram and La Beale Isoud were in prison, it happed a knight and a lady came unto them where they were, to cheer them. I have marvel, said Tristram unto the knight and the lady, what is the cause the lord of this castle holdeth us in prison: it was never the custom of no place of worship that ever I came in, when a knight and a lady asked harbour, and they to receive them, and after to destroy them that be his guests. Sir, said the knight, this is the old custom of this castle, that when a knight cometh here he must needs fight with our lord, and he that is weaker must lose his head. And when that is done, if his lady that he bringeth be fouler than our lord’s wife, she must lose her head: and if she be fairer proved than is our lady, then shall the lady of this castle lose her head. So God me help, said Sir Tristram, this is a foul custom and a shameful. But one advantage have I, said Sir Tristram, I have a lady is fair enough, fairer saw I never in all my life-days, and I doubt not for lack of beauty she shall not lose her head; and rather than I should lose my head I will fight for it on a fair field. Wherefore, sir knight, I pray you tell your lord that I will be ready as to-morn with my lady, and myself to do battle, if it be so I may have my horse and mine armour. Sir, said that knight, I undertake that your desire shall be sped right well. And then he said: Take your rest, and look that ye be up betimes and make you ready and your lady, for ye shall want no thing that you behoveth. And therewith he departed, and on the morn betimes that same knight came to Sir Tristram, and fetched him out and his lady, and brought him horse and armour that was his own, and bade him make him ready to the field, for all the estates and commons of that lordship were there ready to behold that battle and judgment.