LAPD Detective Kate Delafield has a new, iron-willed female lieutenant—a tough new partner who may turn out to be a much-needed ally. She also has a dangerous new case.

A reclusive old man has been brutally slain at the La Brea Tar Pits. The unusual investigation could uncover the truth of humanity's ancient past, and at the same time expose the corruption and violence of the present. And everyone involved—from an alluring scientist with a dark secret to a treacherous CIA officer with his own agenda—is suspect.

With more at stake than just a pile of bones, Kate has to gather together the pieces of a timeless puzzle, and make sure they all fit—before a remorseless killer decides to make her a part of history...