[1] In an elaborate plot to lure Gabriel Allon into a trap, an English royal princess is killed by a bomb.

The princess's life story includes elements based on that of Princess Diana (who died in 1997), as Silva points out in his "Author's Note," but, as he also notes, the bombing of a royal personage on a boat is based on the 1979 death of Lord Mountbatten at the hands of the IRA.

[3] The plot is engineered by the Russian government in vengeance for Allon's interference with their plans in The English Girl (2013).

In this book, Keller confronts old enemies from his stint in Northern Ireland as a member of the SAS Regiment.

Gabriel Allon becomes the father of twins and is on the verge of becoming the director of the Israeli Intelligence Services.