Based on Joe Hill's novel "The Fireman", it's about a worldwide pandemic of spontaneous combustion that will reduce civilization to ashes unless it can be stopped by an improbable group of heroes led by an enigmatic man known as The Fireman. It's no simple blaze: the condition starts as an inky stripe on a bodypart, looking like a tattoo. It's a highly contagious deadly spore that eventually causes the sufferer to burst into flames.
Millions are infected; among them is a nurse who treated numerous sufferers until they eventually perished, with the hospital burned to the ground. Pregnant, she finds herself infected with the spore. Knowing infected mothers have birthed healthy babies, she too is in a race against time.