The opening of the novel shows the children gazing across the Gleam toward the tantalizing hills, deciding to seek “the Unknown” with their rechristened donkey, Modestine. They depart at dawn, narrowly evade discovery by stern Great-Aunt Hewlett (who plies them with hot batch cakes), and breakfast while trespassing in a meadow, where a young landowner, Dick Frampton, indulges their enthusiasm by presiding over a playful “libation” to the God of Adventure; meanwhile, their worried parents search by car but miss them. The trio then meets Montague Francis de Vere, an unhappy boy chafing under a strict great-aunt, who eagerly joins after a hasty clean-up; with the help of a friendly ferryman’s son they cross the river, pass through a scattered village, cross the canal, and climb higher, pausing for a picnic and nap. Tired but elated, they head toward a nearby Priory to ask for lodging, where a genial, attentive man comes to the gate as the scene ends. (This is an automatically generated summary.)