Set in an unnamed fishing village off the north east coast of Scotland, Blyton’s book follows three siblings, Tom and his younger twin sisters Jill and Mary, who are on late summer holidays with their parents.  Their older friend, Andy, is the son of a local fisherman, and the four of them are planning a day trip with Andy’s father’s boat, lent with permission.  On their day outing, a storm sweeps the boat off course, and the four children are shipwrecked on a small island […]