I've just seen Fetching Cody. Here's my thoughts.
Honestly, this is basically just a worse version of The Butterfly Effect. If you like The Butterfly Effect, then you should just go rewatch that, and if you hate it, then you'll hate this one even more.
I mean, so much of this felt like it was a rehash of The Butterfly Effect written by someone who'd heard a plot synopsis of it but hadn't actually seen it. Like, Art goes back to a few different key points in Cody's past to try to save her, keeps failing, and then goes back to prevent his past self from ever meeting her, which is kinda similar to how the end of The Butterfly Effect's theatrical cut goes.
Usually I'm not a big fan of saying that one thing is just a past thing done differently because you can say that about pretty much everything. It's just an overdone criticism, and most of the time it's probably just a matter of it being heavily inspired rather than it being a direct knock-off. Most of the so-called Pulp Fiction knock-offs were just heavily inspired by it rather than just being direct knock-offs.
Fetching Cody did feel like a knock-off version of The Butterfly Effect though, to the point where I sorta wonder if this wasn't initially pitched as a Butterfly Effect sequel.
I wish I could at least say Fetching Cody did something interesting with the premise, but it never really did. The fact that nothing ever really changed after each time he went back in time felt a bit mean spirited, and I feel like it hindered Art's character development more than it helped.
I think it also felt cheap because part of the premise sorta requires a discussion of how much people are a certain way due to life experiences and how much is due to innate nature. This is one of the points where I think The Butterfly Effect did well because at the kind of age the protagonists are at, going back to change this or that life event probably would be enough of a difference to make a difference.
I know there's various different ways time travel can work in fiction, but realistically this sort of story does need to be a form where you can change the past if you go back.
Given that Fetching Cody wasn't really interested in having the timeline change dramatically each time Art went back, maybe the subtext shouldn't have been about how much of a personality is nature vs. nurture. The subtext should have leaned more heavily on the idea that Art really didn't know Cody that well.
That aspect was there a little bit, but it was never the main focus. It would have been more interesting if there'd been a scene where Art says, "I keep going back and seeing how she is at 12, at 14, at 16, and it feels like I never really knew her at all," and Harvey responded with something like, "That's how it is with everyone. You never really know a person until you've seen the way they change with the seasons of their life."
That would have lent a lot more weight to the ending, too. If the movie had have gone that route, there could be the open question of what Art thinks of Cody now that he does know her in ways she'd never allowed him to. While the movie as it exists now has a similar ending and a similar motivation to The Butterfly Effect's theatrical cut, this would have allowed for the motivation to boil down to Art saying, "I don't know how I'm supposed to act naturally around her when I know her in ways she wasn't ready for me to know her in."
Ultimately, this is why I didn't like the movie. It wasn't terrible, but it never went as hard with the premise as it could have, and I don't think it really had anything to say that other movies haven't said better.