The story starts gently enough, with the Brown family going about their normal day, little knowing what the next thirteen days will bring. The family has a history of trade based upon the shipping industry originating on the maternal side. However, on the paternal side; there is a history of sea service within the Revenue and Excise service. The family titular head is away in the American Colonies and has not been heard off for a while, this leaves Mother Brown to run the family business and keep their position in society. There is a paternal Grandfather who is the Commander of the Watchful, (a revenue cutter) but he is in his sixties and this eyesight is failing. Then there is the grandson (Billy) and the grand-daughter (Polly), Billy is at an age where he must reluctantly follow his domineering Mother's advice and join the mercantile side of the family, (much to his annoyance), but he still complies. Whilst Polly is a wayward independent young lady, who has just reached an age where she starts to stand up to her Mother. It turns out after many trials and tribulations that the trading side of the business does not suit Master Brown, especially after American spies hide combustibles and gunpowder under his very nose, secreted amongst the many goods waiting to be shipped. Then, when it is discovered, the traitors want it back. Needless to say, after this, Mother thinks William will be far safer at sea with his grandfather as a Midshipman on his ship. How wrong can she be?