Midnight treasure hunts, fancy-dress parties, and a blue-blooded murder . . . November, 1923. Olive's school chum, Gigi, invites Olive to London because Gigi's dotty grandmother fears for her life--or so she's said to Gigi. However Olive is surprised to find that the dowager is far from muddled. The sharp and imperious matriarch refuses to admit to her worries and sends Olive on her way. Without a client or case, Olive is swept into the glittering lifestyle of the "fast set," and their decadent excess. But then among the cocktails and champagne, a murderer strikes during a frivolous party game, and Olive realizes the dowager's fears were well-founded. Can Olive unmask the upper crust culprit before the party's over for a Bright Young Person? An Old Money Murder in Mayfair is the fifth installment in the popular High Society Lady Detective series from USA Today bestselling author Sara Rosett. Join Olive and her dapper sleuthing partner, Jasper, as they navigate the extravagant parties of the Bright Young People as well as their own budding relationship . . .