Totally Killer (R), on Amazon
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Well, I enjoyed this film a lot more than I expected to. I mean, I figured I'd probably kind of like it, but I didn't expect to love it. And yet, I did. I'm putting my review under "horror" because it's essentially a slasher film, but it could also fit under both "science fiction" and "comedy". I liked the time travel elements well enough, and I loved all the humor, all the 80s references, and how the main character, Jamie, reacted to all the differences between her time and the 80s, especially how problematic the 80s were. I enjoyed the pop culture references, especially Back to the Future. The main time travel premise requires some suspension of disbelief, but I still really liked how it was handled. And, I dunno, it's just a really fun movie in a ton of ways.

The film starts off telling us about three girls who were killed on their 16th birthdays, on October 27, 29, and 31, 1987. Their names were Tiffany Clark, Marisa Song, and Heather Hernandez. On Halloween 2023, a teenage girl named Jamie Hughes (Kiernan Shipka) goes to a concert with her friend Amelia Creston. Jamie's father, Blake, drives them, while her mother, Pam (Julie Bowen), stays home to hand out candy to trick-or-treaters. While Pam's husband and daughter are away, someone comes to her door wearing the same mask the killer had worn in 1987, but that's pretty common in that town, so at first Pam isn't too concerned, but then he pulls out a knife and tries to kill her. She's been worried about this exact situation ever since her friends were killed as teenagers, so she's prepared, and does her best to fight him off. But ultimately, he succeeds in killing her.

Meanwhile, Amelia has been building a time machine disguised as a photo booth at the school's science fair, which takes place on the abandoned fairground that was a popular hangout in the 80s, while it was still active. The time machine was designed by Amelia's mother, Lauren, but she had abandoned it when she couldn't get it to work. But Amelia feels sure her mother was close, and is determined to finish it herself. Then the killer shows up and tries to kill Jamie, who hides in the photo booth. He finds her, and stabs his knife into the control panel, which conveniently turns out to be just what was needed to make the time machine work, and Jamie finds herself in 1987. (The whole "knife completes invention" thing kinda reminded me of the baseball in Honey, I Shrunk the Kids.) She tries to prevent the murders of the three girls, with the help of teenage Lauren, the only one who knows she's from the future. (She tried to warn a couple of cops about the murders, including one played by Randall Park, but they didn't believe her, of course.) Jamie meets her mother as a teenager (played by Olivia Holt), and tries to convince her of the danger by saying she's a psychic, which Pam believes.

So, most of the film is Jamie trying to prevent the murders, and while she does change some things, she is less than successful. Meanwhile, time is flowing at the same rate in the present as it is in the past, and we see Amelia trying to recreate her time machine, and talking with a true crime podcaster named Chris Dubusage, who is obsessed with the killings from 1987. I don't want to reveal too much more, but I will say that Jamie eventually returns to the present, and Lauren gives her a notebook that details all the changes to the timeline that resulted from Jamie's tampering with the past. Which is convenient. I feel like a lot of time travelers, such as Marty McFly, could use a guide like that at the end of their movies. So it was a nice touch, and it was also used as a "where are they now" device" at the end of the movie.