Catherine, the daughter of a knight, lives on a small manor in Medieval England. At thirteen, she is nearing adulthood and spends much of her time trying to avoid boring responsibilities and ladylike behavior.
Catherine's father has decided it is time for Catherine to marry. He treats her marriage like a financial transaction and is planning to marry her off to the wealthiest suitor he can find, despite Catherine's objections.
Remember, Little Bird, in the world to come, you will not be asked, "Why were you not Perkin", but "Why were you not Catherine?"
Catherine does everything in her power to scare away suitors. When the ugly Shaggy Beard insists on marrying her anyway, however, she refuses to accept it. Catherine witnesses the ups and downs of manor life, including marriages, births, and deaths, while trying to figure out how to avoid the miserable life ahead of her.
Catherine finally agrees to marry Shaggy Beard in order to use his money to save an abused bear. Just before his arrival, however, she runs away, unable to face the reality of marriage to someone she detests.
While visiting Ethelfritha, Catherine realizes she cannot run away from her life, but must make the most of it. She decides she can marry Shaggy Beard and still be Catherine. When she returns, home, however, she learns that Shaggy Beard has died.
Shaggy Beard's son Stephen offers to marry Catherine instead. Catherine believes Stephen will be much better than his father and accepts his marriage offer with relief and hope for the future.