Madness is Better Than Defeat by Ned Beauman

In 1938, two rival expeditions descend on an ancient temple recently discovered in the jungles of Honduras, one intending to shoot a huge Hollywood production on location there, the other to disassemble the temple and ship it back to New York. A seemingly endless stalemate ensues. Twenty years later, a rogue CIA agent sets out to exploit the temple for his own ends, unaware that it is a locus of conspiracies far grander than anyone could ever have guessed.

New condition.