With Lieutenant Holbrooke’s promotion, the two lead characters, Carlisle and Holbrooke, have been separated, their adventures occupying alternating books: for Rocks and Shoals, the focus is Captain Carlisle, American captain of a ship of the Royal Navy, navigating the treacherous waters of the St Lawrence River as part of the expeditionary force of General Wolfe against the French in Canada. So the novel exchanges the broad expanses of the ocean for the narrow passages of inland waterways, and ships acting as floating gun batteries alongside infantry assaults: it’s a fascinating insight into an earlier version of combined arms warfare, with the engaging Captain Carlisle as our guide. As enjoyable as the earlier novels in the series.