Blood Ransom. The Shadowboxer Files

For a ghost operative, some jobs are just business. This one is a reckoning. Brill Wingfield, a deniable asset who walks in the shadows, is summoned for an impossible task. Amara Okoro, the Georgetown-educated daughter of a brutal African warlord-turned-statesman, has been snatched in broad daylight from a luxury hotel in Washington D. C. The kidnapping is a professional, silent operation that leaves no trace-only questions.
With the White House in a political firestorm, the official investigation is dead on arrival. The FBI, CIA, and D. C. Metro Police are locked in a bitter turf war, each agency more interested in protecting its jurisdiction than finding the girl. President Okoro, a man with a past as bloody as his country's soil, trusts no one, least of all the American intelligence agencies he believes may have orchestrated the abduction.
Hired as a ghost to operate outside the law, Brill is plunged into a labyrinthine manhunt where every lead is a potential trap. The list of suspects is a who's who of international intrigue:Exiled political rivals hungry for revenge. Islamist militants looking to fund their holy war. Ruthless corporate mercenaries seeking to control a nation's resources. And a violent domestic hate group that sees the President's visit as the ultimate betrayal.
But the ghost has a ghost of his own. Brill's past collides violently with his present when he discovers a link to his own history as a young mercenary in Africa-a past where he fought against President Okoro's bloody coup. Now, he must hunt for the daughter of a man who would see him dead, a man whose most trusted friend he killed twenty years ago.