Clubs for mystery of aficionados are far from a rare sight in Japanese mystery novels post 1980s. Mystery clubs for example play an important role in two of the novels I have translated (The Decagon House Murders and The Moai Island Puzzle), but you see them in plenty of other novels and there are also series that revolve around them. What makes most of these clubs different from the mystery clubs we see in a lot of English-language fiction is demographics: most clubs we see in Japanese mystery fiction are school or college clubs, making both the average member fairly young, but also giving the club and its members a different kind of background setting. There are of course exceptions, with the Art of Murder Club in the Nikaidou Ranko stories being more similar to the ones we see in English-language fiction with people with various ages and professions
The Seven Unravellers in John Sladek's Invisible Green (1977) were a rather diverse bunch too, ranging from a lawyer interested in the legal side of mystery fiction to a low-ranking policeman who seemed a bit too interested in the morbid side of murder. The most colorful person was perhaps Major Stokes, a complete anticommunist nutcase who suspected a conspiracy behind everyone and everything, even among his fellow Unravellers. The members of the club saw each other one last time before World War II heated up to take one group photograph, but then drifted apart. Some of them kept in touch with others, or at least an eye on them, like Dorothea Pharaoh. It was also she who twenty years later decided the Seven Unravellers should meet again. After sending her invitations for the reunion, she is surprised by a phone call by Major Stokes. The War only worsened his paranoid mind and while he's fairly sure Dorothea is one of the good'uns, he can't be sure she isn't watched. He does confide to her that he's close to uncovering a cunning Communist plot to infiltrate British society and that he hopes that Dorothea can pass on a letter with his findings to the right authorities, as he's convinced he's being targeted by a certain "Mr. Green", citing his dead cat and stolen milk bottles as evidence. Dorothea isn't quite sure what to make of Major Stokes, so she decides to hire American sleuth Thackery Phin to keep an eye on Major Stokes to see if he's really in danger, but after a night of surveillance, Phin is highly surprised to find the Major dead in his lavatory. At first sight, it doesn't seem the Major's death could have been caused by anything but an unfortunate heart attack, as there were no signs anyone had entered the house that evening. The paranoid Major had changed his flat in a little fortress with every door and window bolted, and had even left trails of white powder on the floor so nobody could walk around without leaving footprints. The only opening in the house was a little window in the bathroom, but that was hardly large enough for anyone to crawl through. But the timing does seem a bit too good after the Major's warning about Mr. Green and soon after, other Unravellers also find them confronted with color-coded messages, which ultimately culminate in more murders committed by a Mr. Green who can seemingly get in and out any place without ever being seen.
Invisible Green is one of those classics in the impossible crime subgenre that I sorta knew partially already before ever reading it due to references et cetera, so it was perhaps not a completely surprising reading experience. In that sense I think Invisible Green had the misfortune that I had already seen variations on the first locked room murder in other media already that had been worked in more detail. The setting is definitely an alluring one: a miser living in a mini-fortress, a man so paranoid he leaves powder on the floor so he check whether someone is in his house. So how could a murderer even get into such a house and kill the Major in the toilet? I like the trick as a concept: as I mentioned, I have seen this same idea used in more modern mystery fiction too, so it's obvious that Invisible Green was the original source for the trick. The problem is that while the fundamental concept is good in Invisible Green, the details of the story don't really work with the trick: it's not really likely going to kill someone the way it's presented in Invisible Green, not with the house described as it was and how the body was discovered by Phin. In the more contemporary variations I've seen of this concept (which I have read before Invisible Green), the details and clewing were worked out better than in Invibible Green, providing a far more convicing mystery story. Those stories perhaps had the advantage of being written with the power of hindsight, allowing them to alter the trick/setting enough so it is more practically workable, but for me, reading this novel really made me see how those other stories improved on the idea of Invisible Green to make it a more satisfying locked room murder, even if the basic idea is definitely good. It's the small details that make it less convincing in this novel.
After the death of Major Stokes, the remaining Unravellers (and Thackery Phin) decide reunite again to find out who Mr. Green is and whether they are involved with the Unravellers, but more murders follow. I'm not that big a fan of the second murder, which is barely an impossible one and basically only worked because the murderer was extremely lucky. It does feature a nice clue that will ultimately point to the identity of the murderer (though I'd argue that clue could've benefited from more supporting clues). A third murder has an interesting concept, being that that the impossibility mostly revolves around all the remaining suspects being gathered in one house during a party, with the victim being elsewhere. But here you also notice little details that make this plot not really workable the way it is described here: not only would the murderer have made themselves very vunerable for an extended period, the murderer's actions 'post-murder' would also be harder to perform than the story pretends them to be. I don't need naturalistic realism in my mystery fiction, but the moment I try to just imagine the scene as it's explained in the novel, I seem to think of several problems that aren't addressed and which would, at the very least, made the thing a bit harder to pull off.
I might sound like a nagging critic here, but on the whole, I do think Invisible Green is an amusing read. The writing is funny with all kinds of references to other mystery writers (duh, it's about a mystery club) and there's a lot of variety in the plot too. And I am definitely going to read the other novel Black Aura. In the future.
But on the whole, I felt that Invisible Green had a few interesting basic ideas, that could've been worked out better to bring a more convincing product. It stumbles when it comes down to details, details that make the core mystery plots far less plausible than the plot pretends them to be and depending on the reader, that can really kill the experience. It's not completely fair to compare this novel with later stories that reappropiate, and improve on ideas we see here, but I couldn't have planned for the order in which I happened to read these stories and I simply have seen more comprehensive variations on the ideas seen in Invisible Green, which makes the little faults stand out on me.