With the fall of Louisbourg in 1758, the French in North America were firmly on the back foot. Pitt's grand strategy for 1759 was to launch a three-pronged attack on Canada. One army would move north from Lake Champlain, and another smaller force would strike across the wilderness to Lake Ontario and French-held Fort Niagara. A third, under Admiral Saunders and General Wolfe, would sail up the Saint Lawrence, where no battle fleet had ever been, and capture Quebec. Captain Edward Carlisle sails ahead of the battle fleet to find a way through the legendary dangers of the Saint Lawrence River. An unknown sailing master assists him; James Cook has a talent for surveying and cartography and will achieve immortality in later years. There are rocks and shoals aplenty before Carlisle and his frigate Medina are caught up in the near-fatal indecision of the summer when General Wolfe tastes the bitterness of early setbacks. Rocks and Shoals is the seventh of the Carlisle & Holbrooke naval adventures. The series follows Carlisle and his protégé George Holbrooke, through the Seven Years War and into the period of turbulent relations between Britain and her American colonies in the 1760s.

When Spain joined the Seven Years War on the side of France, one of its aims was to conquer Britain’s ally, Portugal. Portugal, meanwhile, was determined to hit back at Spain’s sprawling colonial empire, and the Debatable Lands between Brazil and the River Plate Estuary offered a tempting target.  Finding themselves short of ships, the Portuguese government contracted a London company of merchant adventurers to provide two large privateers as the naval element of the expedition.  In September 1762 George Holbrooke, in his frigate Argonaut, is sent to assist the Anglo-Portuguese expedition. However, Argonaut is not the only man-of-war heading for the River Plate.  He finds a familiar adversary already there, eager to settle old scores. The scene is set for a final battle; the winner will be the captain who can best exploit the shifting sandbanks of this shallow estuary.