A seemingly hopeless trial, with mounds of evidence apparently proving that it was impossible for anyone but the defendant to be the killer... The opening of Strong Poison by Dorothy L. Sayers feels like it could fit naturally into an Ace Attorney game. Unfortunately, as the novel progresses it departs from what appeared to be its premise.
Strong Poison is a fun book and certainly has elements that (may, depending on your preferences) make it worth reading, but is absolutely not the traditional howdunnit puzzle book that it initially appears to be.
Harriet Vane has been accused of poisoning her former lover, Phillip Boyes. The evidence seems conclusive: Boyes was poisoned with arsenic, which Vane was known to have purchased (as part of research for one of her murder mystery novels, she claims). Boyes fell ill almost immediately after visiting Vane's home, and absolutely everything else Boyes ate that day was also eaten by at least one other person with no adverse effects.
Despite this overwhelming evidence, the trial results in a hung jury: one of the jurors simply does not believe Vane would kill someone, and refuses to vote guilty. A second trial (with a new jury) is scheduled for next month. Sir Peter Wimsey (Sayers' recurring detective) also believes in Vane's innocence, and vows to find the necessary evidence to exonerate her by her second trial. Wimsey also begins to try to woo Vane, an endeavor that apparently continues in Sayers' later books.
The book then pulls what feels almost like a bait and switch. Although it seems like the main problem is how anyone but Vane could have poisoned Boyes, the investigation focuses on the motive, with the murder method only addressed in the last dozen pages. While this isn't necessarily a bad thing, it just wasn't what I was expecting based on the set-up. This focus may also have felt more fulfilling if the motive was more interesting; while the motive was a bit more detailed and a slightly different form than usual, it still fell into one of the most traditional archetypes for murder motives.
The other issue with the murder method is that it... isn't actually scientifically possible. To be fair to Sayers, the solution is apparently in line scientific knowledge of the 1930's. We just know now that it's not how certain things work. Also, even if the method was possible, it's clued quite poorly. While the physical components of the murder are fairly clued, the necessary "scientific knowledge" comes out of left field. Sayers also just kind of hand-waves away some of the more incriminating details against Vane.
I thought the first part of Wimsey's investigation was fascinating. Wimsey begins by investigating Vane and Boyes, and I thought it was very interesting how different witnesses painted completely different pictures of the victim and defendant.
However, partway through the book, the investigation then turns to clearly focus on a certain character. While perhaps it would have been interesting if the criminal was someone else, with hints pointing to the true criminal sprinkled into the investigation into the other suspect... the criminal was just the person who was being investigated. This isn't a point "against" the book, but it simply isn't that surprising when the person who has been the focus of the investigation for 100+ pages turns out to be the criminal.
The writing as a whole I felt was quite entertaining, with sharp prose and witty conversations. Some of the investigation sequences felt like they belonged more in a thriller than a detective novel, so they were entertaining and fun to read, but contributed to the bait and switch feel of the book.
There are many references to what felt like contemporary British society of the 1930's, including the divide between social classes and the changing roles and expectations of women. My ignorance in some of these topics made the details of some scenes difficult to understand, but enough is clear from context to follow the plot. Basically, this book may be appealing if you have an interest in British society, especially in the time period.
The characters were overall acceptable for a detective book. Sir Wimsey himself doesn't get much description, so I suppose you're meant to have read another book first. Some characters simply show up without any introduction or description, and I'm not sure whether they truly have no explanation or are recurring from a previous Wimsey novel. Either way, none of the "unexplained" characters are particularly important, so this isn't a major issue.
In sum, Strong Poison is a fun, well-written book, but don't let the premise trick you into thinking this will be a puzzle plot, and you've been forewarned that the solution is based on unclued, outdated scientific knowledge.