This is the first Tommy and Tuppence novel, and it's one of Agatha Christie's series which marks a departure from Poirot's "little grey cells" and Miss Marple's fluffy English village connections. Granted, I love Miss Marple, but I also loved They Came to Baghdad, which was an espionage mystery about archeology.
Tommy and Tuppence, unemployed with limited prospects, decide to enter into the blackmailing business, only to find that they have a flair for crime solving instead. With the support of the British government, they fall in with an American billionaire and attempt to hunt down an heiress who may be holding deadly government secrets. In the meantime, a secret Bolshevik plot to undermine the British government through Labor Day is underway, and only the Young Adventurers can put a stop to them.
About halfway through the novel, Tommy gains some perspective and competence, and as a result, I started liking him. Tuppence is a plucky dame, though she gets fanciful at times, and the two kind of balance each other out. I'll keep reading this series, as it has the potential to be rather good.