Welcome to Edinburgh, 1926. Dandy Gilver, a wealthy and witty aristocrat (and sometimes amateur sleuth) receives a letter from Lollie Balfour, who insists that her husband of five years is having her followed and her mail is being steamed open. The only way for Dandy to help is by pretending to apply for a job as a lady's maid in Lollie's house. Dandy gets a crash course from her own maid and arrives at 31 Heriot Row, ready to put all of her detection skills to good use. Why does Mr. Balfour want to get rid of his wife? And can Dandy stay in disguise long enough to evade the villains?