In 1812, Elinor Pembroke wakes to find her bedchamber in flames—and extinguishes them with a thought. As an Extraordinary, gifted with powerful magical talent, she is respected and feared, but her father intends to control her and her talent by forcing her to marry where he insists. Trapped between the choices of a loveless marriage or living penniless and dependent on her parents, Elinor takes a third path: she joins the Royal Navy.

Assigned to serve under Captain Miles Ramsay aboard the frigate Athena, she turns her fiery talent on England's enemies, vicious pirates preying on English ships in the Caribbean. At first feared by her shipmates, a growing number of victories make her truly part of Athena's crew and bring her joy in her fire. But as her power grows and changes in unexpected ways, Elinor's ability to control it is challenged. She may have the power to destroy her enemies utterly—but could it be at the cost of her own life?