`Let fly jib sheet! Slack away main! Fenders out!' Dick and Dorothea - also known as The Ds - arrive in Norfolk all ready to learn how to sail. They couldn't hope for a better teacher than Tom Dudgeon. But Tom is in a spot of trouble. After seeing the beastly Margoletta moored clean across the nests of his beloved coots, Tom set the motorcruiser adrift. Now the enemy have offered a bounty on his head. Can they save the birds' nest from almost certain destruction? Will they avoid being caught by the awful Hullabaloos? Only some brave friends and quick thinking stands between them and disaster...