The Warsaw Revenant. Marcus Vane Series, #4

For readers of John le Carré, Alan Furst, and Charles Cumming. At the funeral of a retired GCHQ analyst, Marcus Vane sees a man in the third row who has been dead for years. No one else notices. No one else could - the dead man was very good at being dead. What follows is a quiet excavation of a Cold War protocol that was never buried, only waiting: a Warsaw-era operation that learned to survive the fall of the world it was built for, and to adapt to the one that came after.
As Marcus traces the thread from a graveside in London back through decades of controlled silence, he understands that some operations don't end when the war does. They simply change their name. The Warsaw Revenant is a slow-burn, morally grey espionage novel about the past that refuses to stay dead. Book Four of the Marcus Vane series.