I am constantly surprised by how innovative Agatha Christie was. ‘Sparking Cyanide‘ was her thirty-sixth novel. It was published in 1945, twenty-five years after her first book, ‘The Mysterious Affair At Styles‘. It would have been easy for her to live off her reputation and continue to churn out variants of her earlier work and let the public’s appetite for Poirot and Miss Marple keep her in the best-seller lists.

Instead, she tries something completely different and something for which her readers would not have been prepared. She takes the amateur sleuth out of the formula and instead takes us directly inside the memories of the six people who were present on the night that Rosemary Barton died after drinking a glass of champagne dosed with cyanide. As I listened to each of the six people revisiting their memories of that night, a year earlier, four things became clear to me: that Rosemary Barton was not a nice person, that it was very unlikely that she committed suicide, that most of the six people remembering her had a potential motive for killing her and that murdering her without being seen by the other people at the table would appear to be impossible.

I loved that, with each person’s remembrance, my picture of Rosemary Barton and of the people she had been sharing a table with, shifted. It was refreshing not to have my impressions filtered through the, sometimes clumsy or annoyingly smug and gnomic, questions asked by a detective. I felt as if I got to meet each person. Best of all, having met them all and assembled all the facts, I realised that while I knew a lot about them and I knew whether I liked them and whether I trusted them and whether they trusted each other, I still had no idea who the murderer was of how the murder was done.

I enjoyed the character portraits, particularly the one of the political couple, each of whom suspects the other of having committed the murder and the competent but under-valued Personal Assistant, who was always the brightest person in the room and always smart enough not to remind people of that fact.

Then Christie adds another innovative twist: a reconstruction of the evening with the same guests (minus Rosemary Barton) in the same restaurant and with another unexpected death that must be murder and must have been committed by someone at the table and yet nobody sees how it’s done.

In the last part of the book, Christie does bring in some detectives, partly as an aid to exposition and partly to put pressure on the suspect pool. I liked that she didn’t bring in Poirot, whose ego would have cast a shadow over everyone, but instead used two and then three investigators, each of whom added something to the eventual solving of the mystery.

The resolution itself worked but had something of a magic trick feel to it. I was OK with that because, by then, I was more invested in the people than the plot. By taking me inside the heads of six people, Christie made the deaths and their consequences more real than they typically are in a murder mystery. I liked having the human strengths, flaws, relationships and desires being centre stage. This was more satisfying to me than solving a clever puzzle.