Double Indemnity, James M. Cain
A crime noir book, short and quite old. Published as a book in 1943. My first impression was: well, that escalated quickly! Then I found out that it originally ran as a serial in a magazine in 1936, so the pacing was naturally hard and fast without much effort put into serious character development. The love affairs between the characters are largely implied as well to keep the action moving and, I assume, because anything more obvious in the 1930's would've been inappropriate. It's written in first person with a lot of the jargon of the time period laced in, which threw me a little at first. But, surprisingly, it all works.
An insurance salesman plots with a woman to murder her husband and collect the money from his accident policy. They almost get away with it but,of course, they don't and the lesser used love quadrangle (as opposed to triangle) is employed to complicate the situation.
I'd heard of this title for years and have seen some of the story parodied, so it was fun to see the source material in its original form. The fast movement of events made it a compelling read. I think it would've done well as a long form novel that went into greater detail.