Passenger to Frankfurt: An Extravaganza is a spy novel by Agatha Christie first published in the United Kingdom by the Collins Crime Club in September 1970 and in the United States by Dodd, Mead and Company later in the same year. The UK edition retailed at twenty-five shillings. In preparation for decimalisation on 15 February 1971, it was concurrently priced on the dustjacket at £1.25. The US edition retailed at $5.95.

Death Comes as the End is a historical mystery novel by Agatha Christie, first published in the US by Dodd, Mead and Company in October 1944 and in the UK by the Collins Crime Club in March of the following year. The US Edition retailed at $2.00 and the UK edition at seven shillings and sixpence (7/6).