The knight is ordered by the queen to find what women really want. He travels all over asking women this question, only to find all the answers are different. He is in despair because if , at the end of a years time, he does not have the correct answer, he will die.
As he is returning to face his fate, he encounters an ugly, old woman. She promises him the correct answer in return for granting her any request. He agrees. When the knight tells the queen women want to control their husbands in all matters, the queen tells him he is correct.
The old woman tells the knight that she wants him to marry her. With much reluctance, the knight agrees but is horrified by the thought of being married to an old hag. She tells him that he has a choice, she can become beautiful and young yet untrustworthy, or stay old, ugly, and faithful. After much deliberation, the knight chooses for her to remain the way she is. He would rather have trust.
He is rewarded for this, she is young and beautiful, and trustworthy.
The knight has learned that by letting himself give over all control to his wife, whom he is very happy with, he is very content.