A man is the last survivor after an unprecedented war. One day, something, or someone, knocks at his door.

THE FUTURE IS COMING... FOR SOME SOONER THAN OTHERS Ellis Rogers is an ordinary man who is about to embark on an extraordinary journey. All his life he has played it safe and done the right thing, but faced with a terminal illness he's willing to take an insane gamble. He's built a time machine in his garage, and if it works, he'll face a world that challenges his understanding of what it means to be human, what it takes to love, and the cost of paradise. Ellis could find more than a cure for his illness; he might find what everyone has been searching for since time began...but only if he can survive Hollow World. Welcome to the future and a new science fiction thriller from the bestselling author of the Riyria Revelations and the Riyria Chronicles. Sullivan's novels have been translated into fifteen foreign languages and have been selected for more than eighty-five best of the year or most anticipated lists, including those compiled by Library Journal, Barnes & Noble, and Goodreads.