This is one of the best of the Ellery Queen mysteries, although it is rather schizophrenic in structure as well as theme. It starts out with a classic ABC murder plot (a series of killings where the intended real victim is 'disguised' by being one of a group of apparently random murders by some maniac). Halfway through, the murderer is revealed by a bit of luck -- his mistake plus meticulous observation by EQ -- and then the book becomes a cat-and-mouse story with the police trying to trap the killer. And finally, there is a surprise revelation in characteristic Queen manner, including Ellery's typical irritating angst attack, leading him to go off to Vienna on New Year's Eve to consult with an ancient and rabbinical old psychologist. (Note EQ's difficulty in accomplishing the trip -- this is post-WWII, when Austria was still partioned amongst the Allies.)
The serial-killer plot is a good one, with a truly novel solution based on what really connects a bunch of victims with apparently nothing in common. Also, the setting in late 1940s New York City is very well done, with its set piece about the effect on public morale of a random killer called The Cat by the tabloid press. This is effective, if overdone as is usual with an author who indulges in hyperbolic prose -- some could argue very pretentious and overwrought. In some ways, it is interesting to compare this with a real case, the Son of Sam business of the 1970s, where the media frenzy is accurately and amusingly shown, but the fictional events are totally improbable and overdone, with 39 dead after a panic riot during a vigilante meeting and press conference with the Mayor and Police Commissioner.
The entrapment section is more thrillerish, although it is well handled with suspenseful elements, creepiness, and the irresponsible behavior of a couple of Ellery's cohorts (who are typically irritating as a type often used by the author), and Ellery himself bumbling along -- he is not very effective as a man of action. This would make a fine movie, if it were done by a director like Hitchcock. The killer's own frustrations are nicely shown, as are his clever machinations.
Finally, the author has a trademark resolution where it turns out the first solution was mistaken for the most part, at least as to whodunnit. This is effective but it does not quite ring true based on the way the characters had been presented, and it suffers from EQ prose mannerisms such as one-sentence paragraphs consisting of a phrase. Ellery is characteristically guilt-ridden over his perceived 'mistake' and needs to indulge himself with a mea-culpa to a guru figure. (This scene, frankly, is awful.)
In all, I would rate this as one of Ellery Queen's two or three masterpieces. (A reader must be prepared to put up with his flaws as a writer and accept the book as written.) As mentioned, the New York setting is superb and there are some very ingenious plot elements and clues.
Warning: Pretentious writing has always been Ellery Queen's worst flaw as a writer, no matter how clever his plots. (That's why I say you have to take it as written when calling "Cat" one of the best of the EQ's.) Sophomoric/adolescent come to mind. EQ as the sorrowful Young Werther. The books would have been vastly improved with some ruthless cropping by one of the "Black Mask" editors. But no doubt Dannay thought he was writing deathless prose and wouldn't have stomached any meddling.
Grobius, May 2005