Marianne Arnet, young granddaughter of Lord Marlow, secretly publishes Regency poetry under a pseudonym--and she's looking forward to a Marlow-clan visit to London, where she'll meet her pen-pal ""J,"" who so greatly admires the poems of ""Mata."" But before the Marlows arrive, they receive a letter from Jeremy, the Marquis of White-stone, vowing that he and his circle will snub Marianne when she comes to London--because her French father and expatriate mother (who live abroad) are said to be spies for Napoleon! Furthermore, the Marquis' handwriting matches that of Marianne's ""J"" admirer!! So poor Marianne, disappointed and angry, vows to teach the unfair (but super-handsome) Marquis a lesson: she'll appear around London with assorted costumes and aliases--confusing him, tantalizing him, then humiliating him when she reveals her true identity. And things are further complicated by the Marquis' jealous mistress. . . and by the hush-hush London arrival of Marianne's ill, fugitive mother, who reveals that she and papa Arnet are really spies for England. (Of course.) Misunderstandings galore, a big unmasking scene at a ball, and the inevitable happy ending--in another installment of convoluted nonsense from the author of Lady in Disguise, with enough screwball-comedy touches to keep things prancing along cheerily.