Finished reading The Moonflower Murders and immediately started reading Death on the Nile. I liked the first book, but I LOVE the second one. My stereotype of Agatha Christie is that she was one of the world's most inventive storytellers, but her characters were cardboard (I've only read Murder on the Orient Express and The Murder of Roger Ackroyd). But that's not this book at all. The murder doesn't even happen until halfway through the book. The first half introduces the characters--an heiress and the fiance she stole from the woman who's now stalking them--and puts them on a cruise ship down the Nile, then throws Hercule Poirot into the mix. The Belgian detective spends much of his time trying to talk people down and sympathize with them and get them to not act so crazy.
Then a murder happens of course. Not sure how it ends so don't spoil it!
However I realized something while reading the last book, which is that most detective stories come down to motive. Once you can figure out which of the characters has a secret motive for killing which of the other characters, the story is solved. And usually the only reason you didn't get there right away is that the murderer seemed to have no ostensible motive for the killing.
To me, this makes total sense. All the other whodunit stuff is just words on a page. Like who cares about who was where, or about parsing tiny clues. But motive comes down to the very essence of story: what were the lives of these people like before the detective came on the scene? How were they entangled? What's going on in their secret heart?
Now that I know this, I kinda want to write a detective story!