As a Headscratchers subpage, all spoilers are unmarked as per policy. You Have Been Warned.
- Why did Nick conceal Clue 3 from the cops? In fact, he conceals it before he even knows what it points to.
- He stopped bringing the police along on the scavenger hunt when it led to them finding the pair of red panties at his office. He was worried they might be Andie's, and wanted to keep his affair a secret.
- Nick refuses to reveal his alibi to the cops because it's personally damning — his affair with Andi. However, after she reveals the affair and the cops (and public) clearly already hate him as much as they ever well, there's no reason for him to not come forward about that. While he states that their encounter wouldn't exonerate him completely (he also spent some time hiding out in a nearby garage to read old magazines) it surely puts a pin in the perceived timeline formulated by the cops.
- He had two choices. Reveal the affair immediately, or conceal it until it inevitably comes out in the future.
- Revealing the affair immediately may have given him a more believable alibi, but it also gives him a motive (which matches the 'man cave' toys, insurance and financial records) and may have lead to an immediate arrest.
- Concealing it early avoids giving police a motive, but results in any alibi based around it as worthless, because too much time had passed for it to be seen as anything but the mistress trying to cover up for her murderous boyfriend. Had he told them immediately, the Police would have been able to contact Andie immediately, and interrogate her about the affair & alibi with her not knowing anything and thus making her eventual confirmation of the alibi more believable.
- He had two choices. Reveal the affair immediately, or conceal it until it inevitably comes out in the future.
- Why did Amy go to a sketchy dealer to ask to get a gun instead of a proper gun store? Missouri has very lax gun control laws, so that should be easy to do without Nick learning about it. That would also have been much more likely for the police to uncover than the rather random raid at an abandoned building where petty criminals and addicts hang out.
- Amy got a lot of her ideas from true crime books and novels. She formulated her plans based on popular tropes rather than contemporary facts. She's also from the East Coast where gun laws are stricter so even if gun laws are much laxer in Missouri, her instinct is to go through unofficial channels to clandestinely acquire a firearm.
- On a meta-level a lot was made about Nick refusing to wear a Yankees hat, and wearing a Mets hat as a compromise. Why the heck didn’t he just wear a St. Louis Cardinals hat? It certainly would’ve been in character for a native Missourian, and later in the film he shown wearing a Cardinals T-shirt. Besides, even though the Mets are not a bitter rival to Nick’s beloved Red Sox like the Yankees are, they are responsible for arguably the most painful moment in Red Sox history, Game 6 of the 1986 World Series.
- Putting on the hat was the character's way of blending in with the crowd before he got on the plane. Someone wearing a New York sports team's hat in a New York area airport wouldn't draw any attention and could deflect potential recognition. The last thing Nick needed was to be recognized while boarding a plane and spending the next several hours dealing with the harassment.
- What is the deal with Desi? He’s very creepy, but is he also a sociopath or just a control freak? What exactly happened with his earlier relationship with Amy? Did she destroy his life like she did to Tommy? Did he do something to mess her up? Is that at least one of the reasons she murders him? Desi comes from a wealthy family, but apparently isn’t in any relationship despite being a handsome wealthy man. It seems like he was readily available when Amy called as if he was just waiting for her to come back into his life.
- Desi would call himself a romantic, but really he is an obsessive who is too passive to do more than obsess from afar. From what we saw of time Amy was hiding out with Desi, his ideal relationship is one where he dotes on and accessorizes his partner. Amy grew up in a stifling and controlling environment and she would have hated being in relationship like that.
- Movie!Desi has an excuse because these details weren't put into the adaptation, but why did Book!Desi still believe a word Amy said? By their thirties, Desi already knew that either Amy or his mother lied about the latter attacking the former. Then, Nick tells Desi that he thinks Desi had attempted suicide in Amy's dorm bed – another lie. At a certain point, did Desi not notice a pattern that there's always two versions of a story: Amy's version, and everyone else's version? Was the guy just that much of a sucker?
