The Footsteps at the Lock is the second of five novels featuring insurance investigator Miles Bredon. It involves two cousins: one going to the bad; the other, to the worse. The bad: drink, debt, and drugs. The worse: poetry, aestheticism, and Oscar Wilde. There's a grandfather who has written a will that contingently leaves a fortune to the older (bad) one of the cousins, if he survives to his twenty-fifth birthday; otherwise the worse cousin inherits. You see where this is going...
The two cousins go on a canoe trip down the upper reaches of the Thames; the older one disappears. Drowned? Drugged? Murdered?
Partway through the novel a second will appears in which a great aunt leaves an even larger fortune to the older cousin on slightly different terms. The aunt has an adoptive son who might stand to inherit depending on the exact order of everyone's death; Bredon's interest is really only in that question. His friend, Leyland, of Scotland Yard, is naturally more concerned to find the body, and the body's killer, should there be one.
Anyway, pretty amusing. I thought it was a bit overwritten at the start, but it settled down. And while I know pretty much nothing about serious drugs, opium being the drug in question here, I think it's safe to say Ronald Knox knows even less. No doubt that's to his credit. But I suspect everything he knows about opium can be derived from some lurid biography of Coleridge.
So, how does Knox do with his ten commandments? Mostly, I'd say he follows his own rules, but he does rather violate number six:
No accident must ever help the detective, nor must he ever have an unaccountable intuition which proves to be right.He goes to a hotel and unexpectedly discovers a letter waiting for one of the suspects. On the other hand, several of his other rules involve prohibitions against unnecessary duplication--no identical twins! no more than one secret passage!--but not against the duplication of wills, so the letter, if not the spirit, of his commandments is (mostly) preserved.
There is, however, another famous list of rules for mystery writers, that of S. S. Van Dine, and he definitely violates number seven. If you want to avoid spoilers, I suggest you don't follow that link...
And while it's not so very spooky, it is a mystery, and so the first of my RIPXIV books!