Sierra Six Gray Man, Book 11 by Mark Greaney

It's been years since the Gray Man's first mission, but the trouble's just getting started in the latest entry in the number one New York Times best-selling series.

Before he was the Gray Man, Court Gentry was Sierra Six, the junior member of a CIA action team.

In their first mission, they took out a terrorist leader, at a terrible price. Years have passed. The Gray Man is on a simple mission when he sees a ghost: the long-dead terrorist, but he's remarkably energetic for a dead man.

A decade of time hasn't changed the Gray Man. He isn't one to leave a job unfinished or a blood debt unpaid.