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Series Review: 'IKWYDLS' - Does The Season Finale Make Sense?

Madison Iseman and Brianne Tju in I KNOW WHAT YOU DID LAST SUMMER, c/o Amazon Studios
Madison Iseman and Brianne Tju in I KNOW WHAT YOU DID LAST SUMMER, c/o Amazon Studios

By: Kayla Caldwell

Now that we’ve seen the finale of Amazon Prime’s I KNOW WHAT YOU DID LAST SUMMER series - does the ending make sense? First off - there will definitely be spoilers. This entire piece is one giant spoiler, so if you have not finished the series yet, bookmark this until you do. Now that we’ve got that out of the way, the finale reveals the killer, while also leaving the story open enough, should Amazon Prime decide to pursue a second season. So, who is the killer?

Well, that would be my favorite character of the series, Margot, played brilliantly by Brianne Tju. It makes me resent the fact that I spent most of my time watching this, fingers crossed, hoping Margot would survive, so I would get more amazing ensembles and clever one-liners.

In a dramatic confrontation at Clara’s, Alison (As Lennon - from here on out I’ll just write AAL for short, Madison Iseman) finds out that Margot is the killer. Margot knew by AAL’s social media posts that she was certainly not the real Lennon. She tried to believe it when she was away at school, but once they were all together, and AAL kept picking Dylan (Ezekial Goodman) over her, she couldn’t ignore her instincts any longer. Margot's fears are seemingly confirmed when she finds a used condom in AAL's trash can, but AAL lies about it. As Margot begins to reveal her evil plan, she stabs AAL, admonishing her for not coming clean when her supposed best friend, Johnny, was killed.

AAL insists she does love Margot, because “no one’s ever loved me like that before,” and claims Margot is the only one she’s come back to, ever since “that night.” AAL apologizes to Margot, which the latter quips only proves her point, noting, “The real Lennon would never apologize.” Dylan misses all of this monologuing, since he’s been knocked out - most likely by Kyle (Jason Lee Hoy) - and locked in a room. That confrontation had been meant for AAL and Margot, alone.

Eventually, Dylan breaks free, and finds AAL with a knife in her gut. Margot has a gun, but Dylan manages to wrestle it free from her, just in time for Lyla (Fiona Rene) to walk in, and see him holding the weapon. Margot, lightning on her feet, begins to beg for help, claiming Dylan had been the killer all along. Dylan, of course, maintains that this is all Margot and Alison’s fault. This is where AAL can set everything straight… but she decides not to. Instead, she choses the one who had just stabbed her. Even Margot is shocked by this decision, but later uses it as confirmation of their love, saying, “I don’t care what your name is, I have never loved anyone more in my life.”

Brianne Tju, Ashley Moore, Madison Iseman, and Ezekial Goodman in I KNOW WHAT YOU DID LAST SUMMER, c/o Amazon Studios
Brianne Tju, Ashley Moore, Madison Iseman, and Ezekial Goodman in I KNOW WHAT YOU DID LAST SUMMER, c/o Amazon Studios

Dylan ends up in a mental hospital, and AAL and Margot are free to live their lives as partners in crime. Now, I’ve never really been the one to guess all of the twists and turns (ex: I did not at all see “he was dead the whole time” coming when I watched The Sixth Sense). Somehow, the part of my brain that whirs in armchair detective any time I’m listening to a true crime podcast shuts off, so that I can just be along for the ride, like a stoner in a lazy river. For anyone who saw this ending coming, bully for you. To the rest of the twist-ending dummies like me, I decided to give this fun series a re-watch, and see for myself if the clues really do all add up - or if the decision seemed thrown in slapdash, like any season of Pretty Little Liars. So here are my findings.

First of all, Margo was not kidding at the end when she said she “low-key” was trying to tell AAL that it wasn’t about “that night.” Margot tells AAL, “Could be something else you did last summer… or someone?” At one point, when Margot and AAL are sleeping in the same bed, Margot touches AAL’s scars and says, “you have them, too,” meaning she knew it wasn’t the real Lennon.

Some other incriminating quotes:

“You know star-crossed lovers end up dead, right?” - Johnny

“Not always” - Margot (By the end, this applies to her and AAL)

“I’m just saying… people do psycho shit when they’re stressed.” - Margot (Margot would know.)

“It’s classic psychopath behavior to hurt the one you love.” - Margot (This could apply to many of the characters on this show, but definitely Margot.)

“Oh, unless it was like this elaborate plot to send you running into his arms to save you. Trés Swimfan.” - Margot (Sounds a lot like how Margot wooed AAL.)


“Friendships MUST be cherished.” - Margot (She said this while filming an Instagram live at Alison’s funeral… just before going off to kill the deputy and Harold)

“Let’s not forget, Ted Bundy was a gifted person.” - Margot (She says this while trying to blame Dylan)

“As are you, clearly.” - AAL

“I guess you never know what’s going on in the mind of a psychopath.” - Margot (You certainly do not… unless she tells you in a post-credits ending scene.)

“They need a new fall guy now that Clara’s dead.” - Margot (She says this knowing full-well SHE is the one who needs a new fall guy)

Madison Iseman in I KNOW WHAT YOU DID LAST SUMMER, c/o Amazon Studios
Madison Iseman in I KNOW WHAT YOU DID LAST SUMMER, c/o Amazon Studios

Context clues seem to point to Margot, too. We see Johnny tell Margot where he is going before he gets murdered at the school. Also, Margot is constantly putting Alison down in front of AAL. She is a bit of a mean girl, but it still seemed odd to me that she would talk so much shit in front of her supposedly grieving friend. It makes a lot more sense when you realize Margot was probably baiting AAL, hoping she’d finally confess, and admit who she really was.

We know that the dorky cop (Eric William Morris) found out Dale (Spencer Sutherland) was paid in bitcoin from Lennon’s OnlyFans account (which was under Alison’s name). When the password is suddenly changed, Dylan assumes the person who shut down the site is the killer. He was right. We know Margot was in some of those videos with Lennon, so she likely had access to it, too.

Margot makes an excuse to use the bathroom just before two people die at the funeral, claiming she had chugged some weight loss drink beforehand. Afterwards, she’s spotted in the kitchen, right by the scene of the crime. However, no one seems to think that’s suspicious at all, because this tiny influencer was just hiding so she could cheat on her diet with some cake. During the funeral the text, “I’m still here,” is sent to the group. Margot could have sent that because she was confused by AAL kissing her in the diner. It’s also true that some serial killers like to involve themselves in the investigation, and Margot is standing front and center in the crowd when the bodies are discovered.

Later, Margot does call AAL out for kissing her, and then being a bitch, a “classic” Lennon move. This seems like yet another opportunity for AAL to confess, but, as we all know, she again, does not. We also see Margot venting to Riley (Ashley Moore) about AAL, but the latter does not seem to care at all. When they go to Clara’s (Brooke Bloom), Margot wonders, “Since when does she drive with Dylan, instead of me?” And Riley is not interested in her whining, because she snaps, “You sound psychotic right now. Lennon’s fine.” Famous last words. We also know from flashbacks to the party that Margot was jealous of Riley dancing with Lennon, even going so far as to say she looks like a “legit hoe."

We don’t really get a glimpse at the killer when Riley is attacked, nor do we get to see Riley’s expression, since she was stabbed from behind. However, Margot DID get out of Clara's ahead of everyone else, since she left as soon as they heard Clara was back. Is Margot capable of murder? Well, we do know that she has a massive gun closet, and when she got mad at Dylan, she immediately started threatening, saying, “I will take you down so fast.” Margot also seemed ready to shoot AAL’s dad when he showed up after they went to the caves, even though the group had agreed on “no guns.”

There’s a great jump cut from the medical examiner saying someone took care of the spiders and kept them cold, to Margot screaming and jumping after discovering the spiders. That's a nice, little nod to Margot’s status as the killer, before it was confirmed. So there is plenty of groundwork for Margot being the killer - but would AAL really chose her over Dylan?

Not at first, she wouldn’t. But as the show goes on, you can kind of see her falling under Margot’s spell. First of all, when they share that kiss in the diner, Margot may have started it, but AAL definitely kissed her back. And AAL made her father nervous, when he saw her acting all giggly, texting Margot up a storm. “Be careful with Margot. She and your sister were really close. You’re different,” he says, and he's right, of course. But AAL gets visibly butt hurt at the warning, which could be because she is actually beginning to develop feelings for Margot. She also goes to Margot’s place when she’s upset, and climbs into bed with her. They could just be becoming best friends - but there is definitely an underlying romantic tension there.

Madison Iseman and Bill Heck in I KNOW WHAT YOU DID LAST SUMMER, c/o Amazon Studios
Madison Iseman and Bill Heck in I KNOW WHAT YOU DID LAST SUMMER, c/o Amazon Studios

Red Herring Corner:

The biggest red herring is probably Clara, seeing as she has a black truck (like the one that followed AAL, or ran Riley off the road), and her involvement in the cult makes her instantly creepy and untrustworthy. She speaks in almost poetic one-liners, like, “There is no redemption in this life,” and is seen with Alison’s (but really Lennon’s) body, as well as Riley’s.

In a conversation with Bruce, Clara admits that she had held onto Alison’s body (that's actually Lennon's) for a year so she could do a ritual on the solstice, but that she was “not the one.” We see her “preparing the body,” which means covering it in honey (Ah, an explainer for those honey ads), and putting spiders in their brains so that the mind can “be clear, releasing all the guilt and hurt and deceptions.” All of this behavior is massively suspicious, but in reality, we never see Clara kill anyone. We only ever see her with the bodies after they have been killed.

Dylan is another, because he walks around like a moody Twilight character, and clearly has involvements with the cult. He carves Alison’s name on the wall, which is very sketchy, although, like with Clara, we never see him actually hurting anyone. He just follows through with the cult’s “rituals” after the people are already gone. As the show goes on, Dylan’s actions seem more in line with a guilty conscious, or a mental illness. He even admits that due to his OCD, he has to drive around and check in on all of his loved ones at low tide every day. By the end, he appears to be reading the binder that AAL’s mom was looking for, to the other prisoners/patients. He was also the one who sent the notes to AAL, which only adds to the evidence against him.

AAL’s dad Bruce is suspicious, since he was also involved in the cult with Clara. He also lied to his children, since he knew their mother wasn’t actually dead, AND we learn later that he had thrown Lennon out of the car, because he was mad at her. So it was actually his fault that Lennon was in the road that night. We know he’ll do what it takes to protect his daughter, but that’s about as far as this theory went.

AAL’s mom is another suspect. She faked her own death to run away from her family, so her character is in question. She is also dedicated to the cult, and seems desperate to find the binder that had gone missing from Clara’s place. It’s possible she would have killed for the cult or “community,” as she calls it, but we don’t really know enough about her to get to that conclusion.

As is trendy right now, I KNOW WHAT YOU DID LAST SUMMER has a post-credits scene, in which Margot appears to be filming a private video to share with her love, AAL. Here’s what she says happened (and my thoughts on it):

Margot says the cult made it easy to blame things on Dylan, which makes perfect sense (because of what I’ve highlighted above). All she had to do was plant a few items, like Alison’s phone, which she had taken the night of the accident.

Margot had Dale put the goat head in Alison’s closet, but then he was trying to extort her (hence the bitcoin sent from the OnlyFans account), so she had to kill him. And she wasn’t alone. She had Kyle’s help, after he walked in on the “whole Johnny mess.” The dorky cop figured out the bitcoin payments, so Margot had to kill him. Harold was killed just because he was in the wrong place at the wrong time.

Margot says she was fragile after Alison kissed her, but then ghosted her, so when Riley called her a psycho, she used Clara’s truck to hit her on the way out. Dylan also drives a black truck - so that only helped her case at the end. Mei (Margot’s mother, Sonya Balmores) found the strawberry syrup on Margot’s bathroom counter, so she knew she was mukbanging again, and when she confronted Margot, she confessed everything. It was her mom’s idea to frame Clara. Her mom had Kyle steal spiders to put in everyone’s brains, so they would think the murders were cult-related.

Thanks to the seemingly random story Mei tells at the party, about being eight months pregnant and pulling out her Glock to save her husband, we know that she is willing to do anything for her family. Mei also gives Bruce a heads up that his fiancée is looking into his daughter’s case again. It could just be a friend helping out another friend… or Mei did it because she knew the real truth, and knew Bruce would want to keep it hidden, too. This was probably Dylan’s last chance at vindication, but Bruce had already switched the graduation photos after Alison told him what had happened to Lennon, so it made no difference when Lyla had the medical examiner review their photos.

Courtney was freaking out about Riley being missing, so Margot had Kyle take care of her. Clara killed herself, which made things easier for Margot. Then she killed AAL’s mom (Maggie Lacey), after saying she “full-on despises her” for what she did to Lennon. She has Kyle move the body while she does her monologue, so there is no evidence that she’s been killed once the police arrive. That makes it even easier to pin things on Dylan, because he seems like he’s making up stories. Kyle also leaves the body in the cave, which is a location Dylan has been known to frequently visit.

It was Kyle who pushed Margot, which goes exactly to plan, as it makes AAL feel terrible. She tells Margot that she should have been there with her. This is obviously what Margot had wanted, as the “attack” happened at a time when Dylan was getting more of AAL’s attention than she was.

Basically - it all checks out. I kind of love that the girls ended up together, even though they’re both messed up? I feel bad for Dylan, but also, the brutal ending goes right along with the tone of this adaption of I KNOW WHAT YOU DID LAST SUMMER. I mean, it was brutal right from the start. In the original film, the teens accidentally hit a random fisherman. Changing that character into one-half of a set of twins is pretty ruthless.

There are two loose ends that leave the series open to a possible second season. Those are 1) the visual of Dylan reading to his fellow inmates (or patients?), and 2) Riley opening her eyes. Perhaps season two could focus on Dylan growing the cult? It could also have something to do with how Riley is still alive. That part doesn’t make as much sense to me, since her seemingly dead and honey-covered body has been sitting in police evidence for who knows how long, but I tell you what, if there is a season two, I’ll still check in to see how they explain it.

All in all, I KNOW WHAT YOU DID LAST SUMMER was a really fun watch. The outfits and makeup are drool-worthy - especially Margot’s. Tju is an absolute delight to watch, even though if her character were a real Insta-starlet, I probably wouldn’t stand her. The show was entertaining enough, that when I re-watched it for this piece, I wasn’t fast-forwarding or falling asleep at my desk.

Amazon Prime’s I KNOW WHAT YOU DID LAST SUMMER is a worthy addition to the franchise, and, in my opinion, right in line behind the OG film. If for some reason you read this without watching the series, check it out now on Amazon Prime Video.


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