Sad Cypress - Agatha Christie

Christie once again manages to make every single character a possible suspect. I have a theory, though. And if that theory is correct, I´m at a loss for words. Lets see if I can hold a candle to Poirot. Probably not, but anyway. Here is my theory:

 

Dr. Lord acted suspiciously in the last couple of chapters, so I think he actually did it. I think Mary knew that she was the daughter of Laura. And I think Mary and Dr. Lord were an item. Elinor (or maybe Roddy) helped Laura to take her own life, before she could change her will. So Mary and the doctor had to get rid of Elinor in order to get a hold of the money (Mary probably knew that Roddy would inherit the money from Elinor. Mary would then marry Roddy and kill him conveniently off and voilá, Mary would have the money). The good doctor poisoned the sandwiches, thinking that Elinor would eat them, not knowing that Mary would grab a bite as well. 

 

The lesson we all can learn from my theory is: Don´t tamper with the food!

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