What I remember was the book itself was a trade paperback a mostly black background and art of a pyramid with brass colored orbs flying above it in the desert. The title text was blue.
The story is of 2 government men-in-black type agents investigating "Foo Fighters" in Egypt. The 2 agents are a man and a woman and I remember at one point the female agent is very badly injured. It may be part of a series but I'm not sure. UFOs and ancient aliens were big themes. I'm certain it was set in the late 80s-early 90s and made references to the 50s? I dont remember any human antagonists