Don’t Let Go is a kinda-sorta sci-fi crime drama from writer/director, Jacob Aaron Estes, made in association with Blumhouse. It’s a compelling high concept – a cop walks into his brother’s home one day to find his brother and his family (including his young niece, who he was very close with) dead, but he soon gets a phone call from his niece from the past, and proceeds to take advantage of this strange phenomenon to prevent the deaths.

The cop in this case is Detective Jack Radcliff (David Oyelowo), who we initially meet having a pleasant conversation with his niece, Ashley (Storm Reid), after picking her up from a movie. We get a solid two scenes before the film eagerly launches us into the plot proper. Jack walks into his brother, Garret’s (Brian Tyree Henry), home to find the whole family slaughtered, and made to look like a murder-suicide, which becomes the official story due to all the evidence that is rooted in Garret’s criminal and mental illness history.

Jack is understandably overwhelmed with grief, nearly ready to drown himself in alcohol before he suddenly gets a call one day from Ashley. At first thinking he’s going insane, he keeps receiving calls, and eventually comes to the realization that she’s calling him from the past. From here, Jack applies everything he knows about the case to help Ashley give him the clues necessary to find out who is truly responsible for killing them before it happens again…for the first time…in the past. Don’t think too hard about it.

Admittedly, some of the semi-time travel mechanics that the film explores is flimsy at best, but I’ve never seen that as an issue because it is inherent to the genre. Thankfully, the filmmakers know to not focus too much on how this works and why it’s happening, and instead stays in tune with our two main characters and their dynamic. The relationship between Jack and Ashley is really sweet, and it’s not often we see a film explore an uncle-niece relationship in such a positive and charming way.

Much of the film is Jack and Ashley relaying information through each other over the phone, which sounds like it could get old real fast. However, the filmmakers know to keep things engaging. Sharone Meir’s cinematography gives the film a vibe that is both slick and gritty, Ethan Gold’s score highlights the emotional and suspense beats well without being overwhelming, and it doesn’t help that the cast is top notch. Oyelowo is a great lead, bringing in a believable level of desperation, confusion, and heart to the role, and works very well with Reid, who – past the first act – is working largely on her own, and easily carries those moments. Plus, with a supporting cast that includes Brian Tyree Henry, Alfred Molina, and Mykelti Williamson, there isn’t a weak link in the whole film.

Despite all that works, there are some missed opportunities with Don’t Let Go. It doesn’t seem all that interested in exploring the racial dynamic of a black cop in LA and his relationship with his troubled brother, especially given certain reveals that happen later on about the nature of what happened during the murders. It’s not so much an issue that the film isn’t “about race,” but it does feel odd that having a nearly entire black cast doesn’t inform the story in any specific or meaningful way when you know there easily could be. I also wish the film took its time to establish the characters more in the beginning because it got so quick to get to the central conceit that once the plot gets going, almost all the information relevant to understanding the story and the family dynamic is given through exposition when it would’ve been far more impactful if we got to know more about them beforehand. Ashley’s mom also get nothing to work with, barely registering as a character since she barely has lines, and is only seen a couple times not as a bloodied corpse.

It’s certainly arguable that Don’t Let Go is a fairly simple film, with not a whole lot going on under the surface, but as a straightforward genre exercise, I still found it very satisfying. It’s tense when it needs to be, it’s emotional when it needs to be, and the actors bring a lot to make it resonate. The climax is incredibly suspenseful, and practically had me giddy with anticipation as to how it would all end. I’d say that’s a pretty good sign that I was really invested in these characters, and wanted everything to turn out OK for them. While there certainly places where it could have been improved, it still comes together well, and doesn’t risk overstaying its welcome once it’s all said and done. As the summer movie season comes to a close, it’s stuff like this that end up being a pleasant surprise, and this is a cool little movie worth discovering.