[2] The story is set during an alternate-history version of the Napoleonic Wars, in which dragons not only exist but are used as a staple of aerial warfare in Asia and Europe.

The first book of the series tells how Laurence, formerly a Captain in the Royal Navy, becomes Temeraire's handler, and of their early training in preparation for battles against Napoleon's aerial fleet.

In the winter of 1804 ("the year four" as the characters call it) or thereabouts, during the War of the Third Coalition, HMS Reliant under Captain William Laurence seizes the French Amitie, a 36-gun frigate.

Unfortunately, the egg is near hatching, and in order to bring the resulting dragonet into service with Britain's Aerial Corps, it must accept harness and a handler as soon as possible.

Despite Laurence's reluctance to leave polite society and join the Aerial Corps, whose men are almost married to their dragons and who are known for grievous informality, he and Temeraire develop a deep affection.

The spirits of the captains, dragons, and crew are bolstered by the victory at the Battle of Trafalgar (October 1805), which erases Napoleon's navy and diminishes his aerial strength; additionally, while Nelson is raked by fire from a Spanish Flecha-del-Fuego, he survives to fight another day.

While they are celebrating, Rankin and a mortally wounded Levitas arrive at Dover with important intelligence: Napoleon had not planned to send troops over by sea, as originally predicted.

However, Temeraire, earlier deemed unlikely to develop a breath weapon, unleashes a powerful shockwave roar, which destroys the transport they are attempting to take down.