We're into Agatha's 4th decade of writing and the tone of the non-series books has changed a bit. We no longer have the adventure stories with beautiful girls filled with common sense or the English country house murder mysteries. Instead we have intricately plotted mysteries that explore good versus evil. The novels are primarily build up with the actual murder investigation occurring in the last fourth of the book. While the mysteries (or at least the first two) are extremely unique and cleverly done Agatha relies more on coincidence than she has in the past and there is some muddling of details that you won't find in her earlier books.
People are dying and the only thing they have in common is that there names were on a list found on the body of a murdered priest. For the first time without Poirot we have the wonderful mystery writer Adriadne Oliver. She's an almost autobiographical character for Agatha and lots of fun to read. The primary detective is a writer named Mark Easterbrook who becomes involved after witnessing a fight between two women in a Chelsea coffee house and later hearing that one of the women is now dead. The book centers around if it is possible to will someone to death and is very well done. The jump Mark makes to get to the old pub The Pale Horse is kind of unclear and relies heavily on coincidence. Once we get there it's a fantastic puzzle. Ginger is a wonderful character and steals the book from the quieter more thoughtful Mike. 4 Stars
Endless Night (1967)
They say Gypsy's Acre has a curse but young Michael Rogers and his new wife Ellie don't believe it when they purchase the land and build their dream house. They don't believe it when rocks are thrown through the window and when the local gypsy warns Ellie to leave. However, when Ellie is found dead after a riding accident Michael starts to wonder if there could be truth in the curse idea after all. I've read this book several times and know the twist but each time I read it it surprises me. According to her husband this was one of Agatha's favorites and it's clear as to why. 4 Stars
Passenger to Frankfurt (1970)
I'd love to tell you what this one is about but to be honest I'm not really sure. Sir Stafford Nye is a low level man at the state department who started his career on the fast track but then his sense of humor kept causing self-sabotage. It starts out with Stafford Nye getting stuck at an airport and a woman who resembles him asking for his help by allowing her to drug him and then stealing his cloak and passport. After that I can't tell you much. There's lots of political intrigue and a huge quantity of characters and somehow Stafford's great-aunt gets involved. There's a lot of adjectives and rambling descriptions. There's some conspiracies and Nazi tie-ins and a few other things. It's all crammed in to 200 pages and I spent most of that forcing myself to read them when I really wanted to just skim over them. Of all Agatha's 80+ mysteries this is the one I would recommend the least. Really the only reason I finished it was because I'm trying to read all her books. 1 Star