"Murder on the Orient Express" begins on a famed train ride from Istanbul to London. The train is supposed to be vacant this time of the year because it's off-season but instead, this particular coach is unexpectedly teeming with passengers - a melting pot as it were of different nationalities and occupations. Poirot barely gets a seat himself. At midnight, the train halts because of a snowdrift. Poirot hears a mysterious cry in the compartment next to his occupied by an American philanthropist, Mr Ratchet. In the morning he is found dead. And so the question is: who killed him & what was their motive? With a detective on board, things could not have moved quicker.

The book has three neat sections - The Facts, The Evidence and the one where Poirot sits back and thinks by meticulously turning each fact over, and finally, he delivers his two explanations. 

The main element of interest for me about this book is that it is claustrophobic both in terms of atmosphere and the characters: all of the passengers, staff and detective squad are cramped up in a small space, both physically and mentally. Each under the microscopic lens of suspicion and questioning by the little Belgian detective. The ending- I don't know what to make of it except that I didn't expect that of Poirot's judgement. To be fair, I was already spoiled about the ending so naturally, I wasn't in the least bit surprised or shocked by the grand revelation.