"I’m a Stranger Here” could be the song title guiding Lizzie Baker’s life. In the five years she spent on Brown Mountain during the Civil War, Lizzie wanted nothing more than to find the light that transported her back in time and return to the 20th century. While fleeing from bushwhackers in 1864, Lizzie, her friend Abbie Collins, and fiancé Josh Hampton encounter a light Lizzie believes is hers. Hoping to get to safety, she pushes Abbie into the light, expecting Josh to follow. She and Abbie wake to find that this is not the Brown Mountain they remember. Trees and foliage are dying, the air smells like ash, the sky is hazy and dim. And Josh is nowhere to be found.

Shocked to learn they’ve gone forward to the 21st century, Lizzie finds this time strikingly similar to that of the 19th, as the people on the mountain fight for existence in a world that is dangerous and barely survivable. While searching for her fiancé, she and Abbie encounter Jonah Hampton, a man who bears a startling resemblance to Josh. Upon learning that one of Jonah’s ancestors married a Collins, Lizzie begins to suspect that Josh did not come after her but, for some unexplainable reason, married Abbie’s sister Sarie instead.

Once more, Lizzie resorts to practicing herbal medicine by day while frantically searching for the lights by night, although is concerned that going back to Josh could possibly end the existence of people she’s come to care for. To make matters worse, her tenuous relationship with Jonah sets in motion a perilous encounter with an enemy from her past that could lead to her death.

Lizzie faces a hard decision as she continues to pursue the lights, one that will determine her fate for the rest of her life if she finds them: to stay in the 21st century where a war within America looms on the horizon, go back to the 19th century and risk ending the lives of those she’s come to love, or return to the comfort and safety of her time in the 20th century.