Unlike her other novels, it draws inspiration from a documented occurrence; however, the author acknowledges in a note that she has taken liberties with the facts.

[1] The central figure in the novel is Hildegarde Wolf, a fraudulent psychiatrist also known as Beate Pappenheim, who practices in Paris.

[1][2] She finds herself with two patients, both claiming to be Lord Lucan, an English earl who, in a real-life event in London in 1974, mistakenly killed his daughter's nanny, believing her to be his wife.

[1][2] Building upon this premise, the novel unfolds with a series of humorous coincidences and improbable situations, as the two "Lucans" blackmail Dr. Wolf.

In the final chapters set in Africa, there is a reminiscent quality of Evelyn Waugh's novel A Handful of Dust (1934), who was a model and occasional mentor to Muriel Spark.