The Mystery of the Blue Train
is a work of detective fiction by British writer Agatha Christie, first published in the United Kingdom by William Collins & Sons on 29 March 1928 and in the United States by Dodd, Mead and Company later in the same year.<sup id="cite_ref-2" class="reference"> </sup>The UK edition retailed at seven shillings and sixpence (7/6)<sup id="cite_ref-4" class="reference"> </sup> and the US edition at $2.00.<sup id="cite_ref-US_3-1" class="reference"> </sup> The book features her detective Hercule Poirot.
The novel features the murder of an American heiress, taking place on Le Train Bleu. The novel introduces the fictional village of St. Mary Mead.
