Adaptation Displacement: The movie is far more well-known than the novel at this point; people who seek out the book may be shocked that it's a character drama about the guilt the characters feel over the hit-and-run (a little boy in the novel) and having to cope years later while dealing with the title-based note. It's even got to the extent that some reprints of the book have a cover featuring a fisherman with a hook - even though that's something that exists entirely in the movie.
Alas, Poor Scrappy: Barry in the first movie gets killed after he starts to show some Hidden Depths and has spent the day trying to protect Helen. The fact that she - and she does definitely care about him - has to watch him die while people try to stop her from helping makes this even worse.
With regards to Elsa in the book. Although she's jealous towards Helen, there are the occasional Pet the Dog moments - and Helen even thinks back to a "rare moment of sisterly friendliness" when Elsa suggested they move in together. That raises the question of whether Elsa wishes to mend the rift between her and Helen - or she's just The Sociopath who wants to impose on her.
Despite Julie's stance as the responsible one of the group, she never actually stops the others from dumping the body. She just protests it, and never goes to the police herself. She has ample opportunities to stop the others. But she goes along with the concealment and keeps the pact, suggesting she might not be as moral as she paints herself.
Contested Sequel: The second movie has a lot of fans who feel it's an improvement over the first - namely characters like Karla and Nancy proving to be popular, and the setting to still be interesting. Others find it a step down, with a lot of Idiot Ball going around and plenty of Narm in the twists. Fans like to pretend the third movie doesn't exist, but the second is still treated as canon.
Helen, so very, very much. There's no shortage to the fans that wish she had been the final girl with Julie dying.
Karla and Nancy from the second movie are quite popular.
Fanon Discontinuity: I'll Always Know What You Did Last Summer Many fans ignore it for having no connection to the previous two movies, it's been also criticized for it's writing, acting and characters, and there's The Reveal that Ben Willis is now a ghost or zombie.
Julie's love interest in the second movie is played by Matthew Settle. Settle would later become good friends and roommates with Jennifer Love Hewitt's eventual fiancee Ross McCall (and they would also star together in Band of Brothers).
Eventually husband and wife Freddie Prinze Jr and Sarah Michelle Gellar star together. Despite being in a group of friends, their characters only interact once (when Helen looks at Ray before leaving the hospital).
The Dreadful Musician performing during the second Croaker Queen pageant looks uncannily like Reese Witherspoon - Ryan Phillippe's eventual wife, and his and Sarah Michelle Gellar's co-stars in Cruel Intentions. In both films, he gets hit by a car too.
A sisterly rivalry with the eldest named Elsa - jealous of everything her younger sister has? Hmm...
The teens in the first movie, as they decide to throw the body into the ocean to avoid going to jail for DUI and vehicular manslaughter. The Jerk Jockreally crosses the line because he dives in after the body, to make sure it stays sunk. While there, he's the only one who sees the Eye Awaken of the victim, meaning he KNOWS that the victim is still alive! He just swims away, then pressures the others to keep the secret when they start to relent. Of course, the victim had just come back from committing a murder himself, so it's not like he's entirely innocent.
Barry in the book He's the one most responsible, as he was driving, but he's the least affected—his sole concern is covering it up. Then after he's shot, despite knowing full well that the perpetrator is the person who has been stalking the group, thanks to the threatening phone call he received just before it happened, flat-out lies about it, first by claiming that the call was from Helen, thus allowing his parents to blame her for his injuries, then lies to Ray and claims it was a random mugging gone wrong, thus allowing everyone's life to be in danger, proving that he really doesn't care about anyone but himself. It's hard not to feel sorry for a guy who might be paralyzed for the rest of his life, but Barry pushes it pretty close.
Some might say Collie crosses this when he shoots Barry. There's no doubt that he has every right to be angry at the group, but turning them in would be a lot more tolerable than taking the law into his own hands and deciding to KILL THEM all, especially considering that three-fourths of them were genuinely shaken up and sorry about what had happened.
Narm Charm: As noted above, Julie screaming "what are you waiting for, huh!" at the sky is a little silly. But still perfectly reasonable, given the amount of stress the poor girl is under.
After the first film builds a nice amount of tension over who the killer is, he turns out to be someone we've never heard of.
While the first film is thought to be a good one, there are some who feel that an adaptation of the book's plot would still have been good. Though admittedly hard to pull off with the double-identity twist.
Barry knows someone wants to kill him. Said person even tried to run him over. So what does he do? Why, he ends up going up to a dark, secluded balcony all by himself.
Helen is no better. After a relentless pursuit, she runs through an alley and comes upon a parade full of people - only to stop and check if the killer has caught up to her yet. Naturally, she would've gotten away if she had just kept running. Of course, she could not have seen the Offscreen Teleportation coming...
And in the second film, Julie is trapped in a tanning bed that's been turned up to the highest setting. When her friends discover her, they immediately set about trying to bash the bed open. None of them thinks of unplugging it first so Julie doesn't burn to death. There's also Julie going into the tanning bed in the first place and Willis merely trapping her in it. By this point, she had been certain something was wrong, but she leaves herself in a completely vulnerable state anyway. And the guy who has gone to all of this trouble to get her on the island and kill her just continues to play the kind of games that ended up costing him a hand.
The Woobie: Poor Helen. In the book she's from a poor family and continually tortured by her jealous older sister, and in a relationship with a guy she loves but is seeing other people behind her back. She's kind and good to everyone but everyone hates her because of her beauty. While her part in the accident doesn't make her 100% sympathetic, she still goes through a lot. And in the movie her attempts to become an actress failed, and she's reduced to working in the family store (which her sister loves to gloat over). That's not to mention that the killer seems to love torturing her psychologically.
Values Dissonance: Max in the first movie is presented as a Dogged Nice Guy. He makes a move on Julie - when he knows she has a boyfriend - gets very pushy when she politely turns him down, and acts like a jerk to Ray (who is also nothing but nice to him).