Writers, as distinguished from actors or musicians, are in a solitary field. Many are introverts by nature, but even those who aren't basically work on their own, wrestling with their own hangups in order to get something on the page. So there are fewer blowups and confrontations just because so often there's no one to confront.
Still, there are such things as literary feuds. If an author has any success, that can bump up against someone else's success, and then you get into personal clashes. See Mary McCarthy vs. Lillian Hellman, or Gore Vidal vs. anyone.
This time out the victim is one of Ellery's rival mystery writers, Edgar Manning. In a touch you could see as clever or too on-the-nose, he's named after the mystery field's most prestigious award, which was itself named after genre pioneer Edgar Allan Poe. And in fact the story opens with Manning winning a best novel award that's established in-universe as being a pretty big deal. When he accepts the award in public he comes off as merely full of himself, in a way that could be found charming. When he's safely - or not so safely - at home he calls Ellery to, it is obvious, rub the younger author's nose in it. Ellery, home with a cold that will recur as a running gag throughout the episode and keep him, refuses to rise to the bait and in fact tells Manning that he voted for the novel that netted him the trophy. But Manning's revealed himself as something of a cad, and the revelations about his character will only get worse as things go on. You know the drill.
But of course he's gone by that time. Manning mentions something about a rash person come by to balance the books, and then he's murdered, leaving Ellery as an aural witness. It takes a call back after the line goes dead to assess all of what happened. Then Inspector Queen goes out to the house to do some inspecting, reluctantly allowing his ill son to tag along.
Once they get there, the victim's put-upon secretary lays out the scene in perfect detail, unfolding into an uncannily cinematic recreation of the fatal after-party. Flashbacks that are more vivid and detailed than what nearly any person would tell in real life are an old Hollywood custom, of course. Sometimes it's subverted, with The Usual Suspects reaching the height of "never trust a flashback." That's not the case here, as a wrong-footing flashback would make the case impossible to solve before the episode's end.
Anyway, it seems that between his victory and his murder, Manning made sure to alienate about everyone in sight. His research assistant is drunk and bitter, and it's later revealed that the award-winning book was entirely from his own effort. Among his other offenses are playing his publisher and the publisher's ex-wife/competitor against each other, blackmailing his lover, and generally treating his secretary like crap. Most of these people will be satirized in his next novel as well.
As will one other suspect, a hardboiled detective writer pretty blatantly based on Mickey Spillane. This author seems to feel some pressure to be a street-smart tough guy in real life, browbeating other suspects and sometimes threatening to beat up Ellery. Our hero obviously finds this pretty amusing. He towers over the other writer, Nick McVey, of course. Whether I've mentioned this before or not, Jim Hutton was very tall, so much so that he and Paula Prentiss were frequently paired in movies because she was the only contract actress even in range, height-wise. That's not the reason he laughs it off, though, as a burly short man can do damage to a gangly one. But he's spent enough time with Sgt. Velie to know real tough guys don't have to advertise.
For solving the mystery it's helpful to note that if a work of fiction seems a little too quick to eliminate a suspect, there's probably more to the story than you know. Beyond that this one has a few assets in its favor. Jim Hutton has great fun in the central role, confident in his interpretation of Ellery Queen as an eccentric genius whose boy-next-door quality can't obscure the eccentricity or the genius. Two other performances stand out in contrasting ways: improbably glamorous Eva Gabor as the lover with a secret, and Method-intense Dean Stockwell as the frustrated assistant.
Then there's the look. This is one of the most beautiful Queen episodes, due to both the fluid camera work and the mix of Art Deco and Mid-Century Modern interiors. Say what you want about Edgar Manning, but he seems to have had taste.