In British English, the term 'under false colours' refers to the use of a flag to which one is not entitled as a tactic for purposes of deception, and so by extension to any dishonest manoeuver.

[4] Alerted by a twin's intuition of trouble, the Honourable Christopher (Kit) Fancot returns to London at dead of night from his diplomatic mission in Vienna and learns that his brother Evelyn, Earl of Denville, has been missing for a number of days.

What had not been anticipated was Evelyn's continued absence, forcing Kit to maintain the rôle with only the connivance of his feather-brained "widgeon" of a mother, the dowager Lady Denville, and two family servants - his brother's personal attendant Fimber and the groom Challow.

Lady Denville now arrives in state at Ravenhurst, having also invited her elder brother, the miserly Cosmo Cliffe, his wife – who turns out to be a distant connection of Cressy's grandmother and so takes on the role of her temporary female companion – and their son Ambrose, a would-be dandy.

Another addition to the house party is the portly Sir Bonamy Ripple, a wealthy member of the Prince Regent's social circle and Lady Denville's permanent cicisbeo.

Her need to change household at all is because of Lord Stavely's recent second marriage to the jealous Albinia, whose vulgarity is evidenced by her releasing a report to the press hinting at her step-daughter's coming engagement.

The time line of the novel is also established by the reference at the end of Chapter 18 to debt having forced "poor Brummel [to] go and live at horridly cheap places" abroad in the previous year.

[7] In the US the novel was the subject of a long and enthusiastic review in Time, which concluded that "in an age of prurience and pornography, Georgette Heyer's main appeal is in the faultless re-creation of a world of manners and decorum".