Lestrade and the Gift of the Prince. Inspector Lestrade, #9

Book nine in the Inspector Lestrade series. Sholto Lestrade had never smelt the tangle o' the Isles before Arthur, Duke of Connaught put him on the trail to the Highlands. Murder is afoot among the footmen on the Royal Household; a servant girl, Amy Macpherson, has been brutally murdered. Ineptly disguised as a schoolmaster in his bowler and Donegal, with his battered old Gladstone, the intrepid Superintendent is impelled by a villainous web of conspiracy northwards to the Isle of Skye by way of Balmoral. With the skirl of the pipes in his ears and more than a dram of a certain medicinal compound inside him, Lestrade, following the most baffling clues he has yet unravelled, takes the low road alone, save for the trusty yet mysterious Alistair Sphagnum in his twin-engined, bright red boneshaker.
Narrowly escaping the inferno of Room 13 in the North British Hotel, Lestrade falls foul of The McNab of That Ilk and The Mackinnon of That Ilk and plays a very odd game of 'Find the Lady' in Glamis Castle. Coming from Scotland Yard is no help at all to a Sassenach in trews and everyone is convinced it's a job for the Leith Police. Threatened by ghoulies, ghosties and wee, sleekit beasties, Lestrade hears things go bump in the night before solving the case of Drambuie.