In 1808 Kydd leaves his new wife to join Britain’s expedition supporting Sweden in the Baltic. Russia has invaded Finland, Denmark remains hostile and the Russian fleet at St Petersburg threatens the narrow sea routes on which the campaign depends.
Jealous captains and a distrustful commander complicate operations aboard Tyger. Kydd must protect convoys and confront a former ally while manoeuvring through waters where ice, shoals and shifting diplomacy can destroy a squadron as effectively as battle.