A stolen library,

an old adversary,

a league of warriors lying in wait...

When they receive a package from the Warden—the old-school Nazi whose hirelings nearly killed Grant in Arizona—Grant's surprised it's not a bomb but a job offer. The Warden holds the clue to a stash of Italian artworks stolen by the Nazis, which includes a thousand-year-old library stolen from the Jews of Rome. Trouble is, the stash has been tapped to raise money for the Gladio, a secret anti-Communist army established after WWII.

D.A. talks the Bone Guard into taking the job, but how do you know whom to trust when the Nazis write your paycheck? The Gladio leader wants his treasure, the Bone Guard wants to save the library—and the Warden's not saying what she's really after. A young historian helps them sort out the clues, from a ruined town to a buried Flak Tower, but they're completely unprepared for what they find...

When betrayal comes, even Grant can't brace for impact. The Bone Guard returns in their most dangerous adventure yet!