An American heiress nicknamed the Manitou Princess (after her daddy's richest silver mine) is devastated to find that her fiancé only loves her money, so she does what anyone might do: she bolts for Europe, dons male attire and sets out on a walking tour of the Alps. Though professing hatred of all men, she soon falls in with a just-jilted English lord, aptly named Monty Lane, who is attempting to walk off a broken heart of his own. The Princess Passes presents the ups and downs of their alpine relationship through the unpenetrating eyes of Lord Lane. The central romantic action of The Princess Passes recalls comic situations of Shakespeare's cross-dressing heroines and is bookended by automobile-themed sequences as the narrator and friends (hero & heroine of the Williamsons' first novel, The Lightning Conductor) motor south through the magnificent, peaceful mountain passes of pre-World War I Europe.