For Capt. Will Laurence and his fighting dragon Temeraire, put out to pasture in Australia, it seems their part in the war has come to an end just when they are needed most. Newly allied with the powerful African empire of the Tswana, the French have occupied Spain and brought revolution and bloodshed to Brazil, threatening Britain's last desperate hope to defeat Napoleon. So the British government dispatches Arthur Hammond from China to enlist Laurence and Temeraire to negotiate a peace with the angry Tswana, who have besieged the Portuguese royal family in Rio--and as bait, Hammond offers to reinstate Laurence to his former rank and seniority as a captain in the Aerial Corps. Laurence and Temeraire--joined by the egotistical fire-breather Iskierka and the still-growing Kulingile, who has already surpassed Temeraire in size--embark for Brazil, only to meet with a string of unmitigated disasters that leave the dragons and their human friends forced to make an unexpected landing in the hostile territory of the Inca empire, where they face new unanticipated dangers.