The Secret of Chimneys is a work of detective fiction by British writer Agatha Christie, first published in the UK by The Bodley Head in June 1925 and in the US by Dodd, Mead and Company later in the same year. It introduces the characters of Superintendent Battle and Lady Eileen "Bundle" Brent. The UK edition retailed at seven shillings and sixpence (7/6) and the US edition at $2.00.

The Koh-i-Noor, also spelled Koh-e-Noor, Kohinoor and Koh-i-Nur, is one of the largest cut diamonds in the world, weighing 105.6 carats (21.12 g). It is part of the Crown Jewels of the United Kingdom. The diamond is currently set in the Crown of Queen Elizabeth The Queen Mother.