Christopher Booker is a scholar who wrote that every story falls into one of seven basic plot structures: Overcoming the Monster, Rags to Riches, the Quest, Voyage and Return, Comedy, Tragedy, and Rebirth. Shmoop explores which of these structures fits this story like Cinderella’s slipper.
Plot Type : Voyage and Return
Anticipation Stage and 'Fall' into the Other World
Custance receives a proposal of marriage from a Syrian Sultan, which her father decides to accept upon the Sultan's promise to convert to Christianity. Never mind that Custance has never been to Syria. To her, it is a strange and alien land full of people of unknown "condicioun" (271). But voyage there she must, because she is a woman, which means she's got to do whatever the men-folk say.
Initial Fascination or "Dream Stage"
Custance makes a triumphal entry into Syria in a great procession, where the Sultan's mother and the Sultan greet her warmly. The Sultan's mother even throws a huge party for her. Everything seems to be going so well...
Frustration Stage
Unbeknownst to Custance, the Sultaness has conspired to kill all her companions and set her to sea in a rudderless boat. Custance drifts to Northumbria where she marries its king, but again, another evil mother-in-law plots to unseat her.
That's right: a shadow falls over Custance's journey in the form of not one but two treacherous mothers-in-law who are unhappy about her marriage to their sons. The shadows darken when Custance drifts aimlessly at sea for years. They begin to lift when she gets to Northumbria and marries the king. Unfortunately, though, the evil hasn't been vanquished, and as the second mother-in-law sends her false letters, the shadow begins to darken again.
Nightmare Stage
Custance's nightmare occurs more than once, when she drifts helplessly at sea after her mothers-in-law conspire to set her adrift there. It doesn't seem like Custance is going to make it—who could survive in a tiny rudderless boat on the open ocean? Luckily, the hand of God is at work in our story.
Thrilling Escape and Return
In the course of her second voyage, Custance meets a Senator of Rome who takes her home. There, she eventually reunites with her husband. Custance hasn't been changed by her journey—she has always been and will always be a pious, faithful, and steadfast Christian—but her journey has changed the world by spreading Christianity to Northumbria.