The summer of 2024, when Solar Cycle 25 reaches its zenith is a time of auroras and adventure for Marty Clark, high school graduate, and her former tutor, Cy Riverton, age 18, a physics and math prodigy entering the master's program at the university. For Cy, the hike to Dead Man's Drop Cliff means gathering information to solve the toughest physics problem he has ever faced: How did his friend, Eddie Burrows, disappear from there during 2024 Spring Break and end up in Pennsylvania in the year 1857? Marty joins the hike to spend time with Cy, someone she hopes will someday be more than a friend, just days before she is to leave on a two-month history immersion tour. She has no idea just how immersed in history she will shortly become. As a joke, Marty calls Cy's cell number while on Dead Man's Drop Cliff. That starts an adventure through time that takes her from 1748 western Pennsylvania to 1758 Maryland where the fox terrier, Hunter, joins her. She befriends a Lenni Lenape woman, Green Corn, and stays with an colonial Englishwoman, Maggie. While trying to decide the culture in which she could live a happier life if Cy cannot figure out how to get her home, she finds herself threatened by tribal warriors and British colonists alike. Only after Marty disappears does Cy realize how much she means to him. He communicates with Marty using text messages while he evades pursuit by FBI Special Agent Lee Hardin who remains suspicious of Cy's involvement with Eddie. Will Cy and Marty discover how to become reunited before time has run out for them?