It is the first novel in a trilogy featuring former MGB Agent Leo Demidov, who investigates a series of gruesome child murders in Joseph Stalin's Soviet Union.

[2] The second and third books in the trilogy, titled The Secret Speech (April 2009) and Agent 6 (July 2011), respectively, also feature the protagonist Leo Demidov and his wife, Raisa.

[8] The Sunday Telegraph praised it as a "memorable debut": "the atmosphere of paranoia and paralysing fear is brilliantly portrayed and unremittingly grim".

[13] This view was mirrored by a further review for The Guardian, by Angus Macqueen, who stated that while "this is a compelling detective story", "the desire for the plot to encompass every element of Soviet history eventually overrides any sense of artistic seriousness".

[15] In 2008, it was named on the longlist for the Man Booker Prize, nominated for the 2008 Costa First Novel Award, and received the CWA Ian Fleming Steel Dagger for best thriller of the year from the Crime Writers' Association.