Alan Garner's The Owl Service

Alison and her step-brother, Roger, are spending a few weeks of the summer in Wales at a house formerly owned by Alison's late father. After discovering a set of dinner plates in the attic, Alison traces the plates' flower pattern onto paper, discovering that they fold in turn into owls. Soon, the house starts to reveal hidden secrets, compelling Alison to experience an ancient legend brought back to life...