Emissary — Chris Rogers

On a desperate mission to save his entire race from extinction, Emissary Ruell travels to Earth equipped with his two most powerful bargaining currencies -- health and longevity -- hoping to convince the most powerful leader in the free world that collaboration can save both of their civilizations. Having no way to communicate directly with humans, Ruell must inhabit President Addison Hale's body to carry out his mission. He quickly discovers, however, that humans are more complex and volatile than anticipated. Only after admitting defeat does he encounter Kirk Longshadow, and ordinary cop who might be Ruell's last chance.