Mack Bolan agrees to bury the hatchet with the CIA to help and imperiled Company mole in Moscow. Under official U.S. sanction the Executioner penetrates the Kremlin with a personal vendetta in mind. Nolan ends the blood feud when he buries the hatchet deeper than anyone expects: right into the heart of the troubled KGB high command.
Used availability for Don Pendleton (House Name)'s Moscow Massacre
August 1986 : UK Mass Market Paperback