This is the best Christie I have ever read! It is different to her usual whodunnits and yet is just as thrilling. Tommy and Tuppence, the two main characters, have been friends since childhood. In a tea room they sit and discuss the difficulties of finding work after the war and decide to start up their own adventure company, a kind of detective agency. This opens up a spiralling story of mystery and suspense. The opening prologue works really well in setting the scene. A sinking ship and a man handing over important documents to be delivered, to the appropriate people in London. This reminded me of films such as the "The Thirty Nine steps" and "The Lady Vanishes". Indeed the book has a very similar style to these films, which I enjoyed as it had a certain charm. The characters are very likeable and again owe something to the earlier mentioned films. Margaret Lockwood would make a good Tuppence and Robert Donat a perfect Tommy. Mr Brown is the illusive villain of the book, which adds another important element to the style of the story. This story was I believe, the second one Mrs Christie published, after a Poirot yarn. It seems a shame Tommy and Tuppence did not become as popular as Poirot or Marple. Tommy and Tuppence have to track down Jane Finn, a name they overheard in a tea room, that later surfaces again in a very different light. Agatha Christie once overheard a person talking in a tea room about someone called Jane Fish and she thought it would be good to use the idea of a strange name being overheard and later being used again in a different context - changing it to Finn as Fish sounded silly! The details of London in this book make it a particular delight to read. From the Lyons Tea shop to the now closed Dover street tube station, make the reader feel part of that time. I would recommend this book to all Christie fans and those more familiar with her sleuths, as these characters will be a welcome surprise.