[2] Blending steampunk with urban fantasy, Heartless is set in an alternate history version of Victorian era Britain where vampires and werewolfs are welcomed as members of society, often in the upper class.

The protagonist of the novel is Alexia Tarabotti, the Lady Maccon, who is "soulless", and thus unaffected by the powers of supernatural beings.

To make matters worse, her sister Felicity has become a suffragette, something odd has taken up residence in Lord Akeldama's second best closet, and London is suffering a plague of zombie porcupines.

On September 22, 2010, the author reported that the manuscript was "99% complete" and that the final draft of the novel was due to the publisher on November 1, 2010.

[4] In their May 2011 review, Publishers Weekly said of Heartless that "Carriger's writing remains crisp and witty, and the affectionate banter between Lord and Lady Maccon will please series fans distressed by their long separation in 2010's Blameless.