1804: Britain is at war with Napoleon’s France. Captain Sir Richard Giles is enjoying a well-deserved break at his home, Dipton Hall, before being assigned to a new naval mission. News arrives that his half-brothers are dead. Giles is their heir, but they leave him more problems than rewards. Any difficulties that he cannot straighten out himself will have to be resolved by his wife, Daphne. After introducing her to London life, he takes her on the maiden, shake-down cruise of his new frigate, only to have the interlude at sea include a battle with an equally powerful French vessel.
Giles’s mission involves his going to St. Petersburg carrying with him an obnoxious special envoy. Giles himself carries the terms for a special, secret naval treaty. All is not smooth sailing for him in the Russian capital as he must evade both suspected spies and also the enthusiastic efforts at seduction by some noble ladies. At the same time, his own crew brings dishonor on his ship.
His contacts with the Russian Navy at their principal base of Kronstadt go much better than did his social life in the Russian capital. He engages in a competition with the cream of the Russian navy. Evicted from St. Petersburg due to the special envoy being declared persona non grata, Giles must aid his friend Captain Bush to defeat two French frigates in order clear the way for him to return to Daphne.
Meanwhile, despite her being pregnant, Daphne is left to straighten out the mess left by the death of her older brother-in-law. This involves her plunging reluctantly into the seamier side of Georgian society. It seems that her husband has been totally entangled in a web by which he must support a most disreputable business. Daphne uses bluff and guile to turn the tables on her sleazy opponents and to escape, with a profit, the web in which she appears to be trapped.
Back at Dipton Hall, Daphne gives birth to her son, but her recovery from the ordeal is cut short by the need to outwit a plot to wrench control of her husband’s rotten borough from Giles’s control and to counter the ill-will of the man who tried to steal the election. Her difficulties are only resolved by the fortuitous return of her husband who outwits their nefarious rival despite being himself seriously wounded.