For Valour: Andy McNab's best-selling series of Nick Stone thrillers - now available in the US

When a young trooper is shot at the Regiment's renowned Killing House at the SAS's base in Hereford, Nick Stone is perfectly qualified to investigate the mysterious circumstances more deeply.

But less than forty-eight hours later, a second death catapults him back into the firing line - into the telescopic sights of an unknown assassin bent on protecting a secret that could strike at the heart of the establishment that Stone has, in his maverick fashion, spent most of his life fighting to p...