When Roger, Diana, Snubby and Barney go on holiday to Ring O' Bells village, they are eager to explore the secret passage in Ring O' Bells Hall. Is it really a dead end as they have been told, or does it follow the route marked on the old map they find?
It's the end of the Easter holidays, and the children are due back at school. But, in one of Blyton's tried and trusted plot devices, the children are still recovering from 'flu and need a short holiday away! Mrs Lynton phones her old governess, Miss Pepper, and asks if she can suggest anywhere that might do, somewhere with plenty of walking trails. It turns out Miss Pepper has a cousin who keeps a little boarding house in the village of Ring O' Bells, near Lillinghame, and this village has stables, woods, hills... everything children need for some good fresh air and plenty of exercise.