Semper Mars (Heritage Trilogy #1)

The Year is 2040.

The Marines have landed on Mars to guard the unearthed secrets of an ancient and dangerous alien race: Ourselves.

Scientists have discovered something astonishing in the subterranean ruins of a sprawling Martian city: startling evidence of an alternative history that threatens to split humanity into opposing factions and plunge the Earth into chaos and war. The USMC -- a branch of a military considered, until just recently, to be obsolete -- has dispatched the Marine Mars Ex...