Graham, Heather. Blackbird files.

"In the streets of Paris, someone wants to paint the town red... When Special Agent Jeannette LaFarge is called in to investigate a vineyard in the Reims region of France, the last thing she expects to find is multiple bodies with every vein bled dry. It's yet another case tailor-made for Blackbird. Joining her is recent recruit Detective Daniel Murray, eager to use his newfound abilities to track down whoever is terrorizing Paris and its surrounding areas. With each ashen victim grows the realization that those responsible weren't inspired by vampiric creatures of the night but by Elizabeth Báthory herself. The Hungarian noblewoman's unspeakable crimes against her people are being reenacted in both the City of Lights and across the French countryside. Unless the two of them act quickly, the upcoming harvest promises to yield blood instead of wine" --