The Demon Crown (Sigma Force Series)

A construction project beneath the National Mall reveals a dark secret dating back to the Civil War, something buried by a cabal of scientists, led by Alexander Graham Bell, who helped found the Smithsonian Institution. It is a cache of bones, preserved in amber, protecting a wonder like no other, the very secret of life after death. But such a prize is guarded by a horror out of the ancient past, a horror that still lives in the marrow of those bones-and is now free again. From a crystalline…