My extreme antipathy towards Rian Johnson left me with no interest in seeing Knives Out, much as I love good mystery stories. I still haven’t seen it, but I have learned the solution from someone who did, and, having confirmed it by a perusal of Wikipedia, I am about to say something about it. Though take it with a grain of salt.
Needless to say, SPOILERS, and spoilers of a mystery, which is worse. However, quite frankly the solution is so stupid that I don’t think it matters.
So, the solution, described by wikipedia, is this:
Unknown to Blanc, after the party, [Christopher Plummer]s nurse, Marta Cabrera, accidentally administered him an overdose of morphine instead of his usual medication and could not find the antidote, leaving Harlan minutes to live. To protect Marta, Harlan gave her instructions to create a false alibi to avoid suspicion over his death; he then slit his own throat. Marta carried out Harlan’s instructions, but Harlan’s elderly mother saw her and mistook her for Ransom.
…After Ransom learned at the party that Harlan was leaving everything to Marta, he swapped the contents of Marta’s medication vials and stole the antidote so she would kill Harlan with an overdose of morphine, making her ineligible to claim the inheritance by the slayer rule. However, Marta actually administered the correct medicine without reading the labels, recognizing it by the weight and viscosity of the fluid, and is therefore innocent of Harlan’s death. After the death was reported as a suicide, Ransom anonymously hired Blanc to discover Marta’s guilt. Fran later saw Ransom stealing Marta’s medical case to hide the fact that the contents of the vials had been switched, and sent him the blackmail note.
So, the trained nurse couldn’t recognize the symptoms of a massive morphine overdose? Neither she nor the old man himself realized that he was wide-awake, perfectly lucid, and mentally alert enough to be able to concoct a complicated plot in the space of a few minutes, despite supposedly getting a lethal overdose of a sedative? In fact, the old man was so convinced that he had mere minutes to live that he cut his own throat some five minutes after getting what he thought was a massive overdose of tranquilizer, enough to kill him within mere minutes?
If he had gotten that level of an overdose, it would have hit him hard straight away and probably left him all-but incapacitated at once, if it didn’t actually put him straight to sleep. He certainly wouldn’t be coming up with elaborate false alibis or cutting his own throat minutes later. It’s a narcotic; you would feel it if you got that much all at once, you wouldn’t be fully functional until the timer runs out like in a video game.
I’ve heard the film compared with the works of Agatha Christie. Dame Christie would have tanned your hide for this. Her solutions were sometimes a little wonky, requiring luck and split-second timing, but they didn’t turn on people simply forgetting how drugs work to the extent that they kill themselves over it. In one of her stories, this would have been the unworkable fake solution disqualified by requiring totally unreasonable behavior on all sides. I can just picture Poirot: “Does a man who has just been given 20 ccs of morphine concoct an elaborate alibi for his nurse and then calmly cut his own throat? Would he even remain conscious long enough to learn that a mistake had been made? And does a trained nurse mistake a wide-awake man who is calmly conversing with her for a man who has just been lethally drugged with a narcotic? No, no! C’est impossible!”
Why didn’t the grandson just mix the two instead of swapping completely? Blend in an amount of morphine to the medication, and the same result ensues, only without the stupid element of the man coolly and deliberately cutting his own throat because both he and his nurse thinks he’s been given enough morphine to knock out an elephant, and still believe it after five minutes of intense, lucid concentration? Even if they find the mixture, it would be all-but impossible to pin the blame on any one person, and she would still come under suspicion either for incompetence or murder (but you could easily arrange for the mixture to be covered up somehow).
Actually – again, speaking without having seen the film – wouldn’t that make for a better story? She legitimately did kill him, and the detective has to prove it wasn’t her fault?
Or if you wanted this particular set up, just have the medication be something that wouldn’t affect his mind, like the ever-handy digitalin. See, that’s the worst part of this sort of thing; it would be so incredibly easy to avoid this problem with just a little bit of thought. You can have everything the same (though the suicide angle still seems wonky to me), only without the glaring gap in logic. But they didn’t care enough to even do that, apparently.
You know, with so many people praising the film, I thought perhaps that meant that Rian Johnson actually could write a decent story, just couldn’t do Star Wars. But, no; at least as far as the solution goes, this film shows the same level of blind stupidity as The Last Jedi: an inability to think things through or give people logical motivations or reactions. Characters just do what they are told because they’re told to do it because he doesn’t know how to get his desired effects otherwise.
If he doesn’t start to improve, his oeuvre is going to be a treasure trove of “don’t do this” examples for future writers if nothing else.