Nightfall Bay — Carolyn J. Rose

When her grandmother dies, Rain Paxton inherits an extraordinary gift -- the ability to follow a phantom dog into the afterlife, to a place called Nightfall Bay. There, at the edge of a dark sea, the souls of the missing and murdered must wait for earthly mysteries to be solved. Pierce Jennings is a wealthy man, rich enough to fund a crime task force. But money can't buy what he wants most -- to know whether his wife is dead or alive. Missing more than two years, Ariel is one of a dozen women taken by a serial killer known as the Peddler. Drawn to Pierce, and longing to learn Ariel's fate and free the souls of the Peddler's victims, Rain prepares to journey to Nightfall Bay. But the Peddler will kill to keep her from speaking with the dead and revealing his identity.