No one knows exactly when it began or where it originated. A terrifying new plague is spreading like wildfire across the country, striking cities one by one: Boston, Detroit, Seattle. The doctors call it Draco Incendia Trychophyton. To everyone else it’s Dragonscale, a highly contagious, deadly spore that marks its hosts with beautiful black and gold marks across their bodies—before causing them to burst into flames. Millions are infected; blazes erupt everywhere. There is no antidote. No one is safe.

Harper Grayson, a compassionate, dedicated nurse as pragmatic as Mary Poppins, treated hundreds of infected patients before her hospital burned to the ground. Now she’s discovered the telltale gold-flecked marks on her skin. When the outbreak first began, she and her husband, Jakob, had made a pact: they would take matters into their own hands if they became infected. To Jakob’s dismay, Harper wants to live—at least until the fetus she is carrying comes to term. At the hospital, she witnessed infected mothers give birth to healthy babies and believes hers will be fine too. . . if she can live long enough to deliver the child.

Convinced that his do-gooding wife has made him sick, Jakob becomes unhinged, and eventually abandons her as their placid New England community collapses in terror. The chaos gives rise to ruthless Cremation Squads—armed, self-appointed posses roaming the streets and woods to exterminate those who they believe carry the spore. But Harper isn’t as alone as she fears: a mysterious and compelling stranger she briefly met at the hospital, a man in a dirty yellow fire fighter’s jacket, carrying a hooked iron bar, straddles the abyss between insanity and death. Known as The Fireman, he strolls the ruins of New Hampshire, a madman afflicted with Dragonscale who has learned to control the fire within himself, using it as a shield to protect the hunted . . . and as a weapon to avenge the wronged.

In the desperate season to come, as the world burns out of control, Harper must learn the Fireman’s secrets before her life—and that of her unborn child—goes up in smoke.