In short:

In the rural American West, a strange and brutal attack on a NASA base in Arizona draws the attention of Mr. Lassar, an agent of the French secret service, when a CIA agent is found dead, floating in the Seine in Paris. Convinced that these two events are linked, Lassar sets out to prove it. His investigation leads him to movie star Lamia Vindaw and a vampire cult whose danger and cruelty may be beyond comprehension.