Connor Smith works for Primrose, an organization tasked with monitoring and tracking aliens and alien technology. It's a job that doesn't know the meaning of "nine-to-five". It also doesn't leave much room for a social life, a complication that Connor hasn't minded, until now. At the prodding of his best friend, Connor reluctantly puts himself back in the dating pool, even though it means lying about his remarkable life. Elsewhere, Noah Jones has led a remarkable life of his own. Stranded on Earth in 1648, Noah was forced to transform himself permanently into human form to survive. He soon learned that in doing so, he'd become effectively immortal, aging only at a glacial pace. Alone, with no way to contact his people or return home, Noah becomes a silent observer of human civilization—always in the world, but never of the world. Then, hundreds of years later, he sees a face in a crowd and instantly feels a connection that he thought he'd never feel again. But he's too late: Connor's already taken. Destiny is not without a sense of humor, though, and the two men are pulled inexorably closer, snared by the same web of dangers and conspiracies. Worse, Primrose is now aware of Noah, and they aren't ones to leave an alien unrestrained. So while Connor struggles to understand the strange pull he feels toward Noah, forces without as well as within are working against them to keep them apart.