Land of Ghosts — E.V. Seymour

Seconded from MI5 to the SIS, Tallis must take on his most explosive mission yet. A series of high profile killings has made the Russian government increasingly authoritarian. And for Paul Tallis, former elite firearms officer and currently working off the books for MI5, the crumbling international situation is about to become very personal.

Unknown to Tallis, his old schoolfriend, Rufus Graham, has been working deep undercover for the Secret Intelligence Service in the Chechen mountains. When it's feared that Graham has turned rogue agent, Tallis is tasked with finding his old friend and bringing him back home. But for the first time in his life, Tallis is forced to question not only the legitimacy of his orders, but whose side he wants to take.