As a San Francisco homicide detective, Mari Lucas was used to calling in favors to get her sister, Kerry, out of trouble, but this was the last straw. Instead of her usual minor brush with the law, Kerry landed herself in a locked psychiatric ward rambling about vampires who were out to get her. Working in San Francisco, Mari had seen a lot of crazy things, but vampires? Maybe Kerry had finally lost her mind.

But when her sister goes missing from the secure psychiatric facility, Mari is forced to investigate her disappearance along with a disturbing increase in missing persons cases among the homeless population. Forced to work the case with an outside detective, Mari will stop at nothing to find her sister. But what she finds will change her life forever.