Agatha Christie seemed to have a bit of a thing about murders either on trains, or observed from them. Sadly, The Mystery of the Blue Train is no Murder on the Orient Express or 4.50 from Paddington. This 2006 dramatisation is still a good yarn, though, typically sharp and glossy.
Poirot (David Suchet) boards Le Train Bleu bound for the French Riviera in the company of a young lady (Georgina Rylance). Now, don’t get the wrong idea; there’s no funny business. She’s merely a rather shy and awkward young heiress to whom he’s taken a shine. (Actually, she’s an ingenue of the most astonishing drippiness, but Poirot doesn’t seem to notice.)
The train’s packed with the very rich – playboys, gamblers, wealthy young women – and is thus a hotbed of intrigue, villainy and deceit. When a body is discovered in an adjoining sleeping compartment, the great man and his little grey cells are quickly on the case.