Left an orphan after a sheltered life, Verity is sent by her aunt to a co-educational school in Wales where her cousin, Daffila, is already a pupil. Verity dislikes her cousin and hates the Welsh mountains but she makes friends with Gwenllian, a mysterious girl who is miserable because she is not allowed to do any climbing. During a terrible blizzard and flood it becomes necessary for someone to cross the mountains for a doctor.

Felicity is dismayed to learn that she must leave her beloved coeducational school in Wales and go to a girls' school in Switzerland.