Mercy - Michelle Larkin

FBI Special Agent Mercy Parker has never shied away from a difficult case. But finding and stopping the man who plans on single-handedly annihilating the human racearmed only with her 9mm, integrity, and sense of humoris definitely not in her job description. Perhaps it's time to ask for some help.
Psychic ex-profiler Piper Vasey keeps everyone at arm's length, but Mercy's wit and selfless dedication to the greater good slowly break down Piper's defenses. As their attraction for one another grows, they're joined by an unlikely team of extraordinary people. Together, they embark on a race against time to recover a journal, a dog, and a kidnapped girl with unique psychic abilities.
There's a slim chance they'll succeed in saving the human race, but will it be enough to restore the balance between unseen forces of light and darkness that have plagued humankind for centuries?