Scott Wise’s review published on Letterboxd :
When's the last time you saw a good mystery horror? If you, like myself, had your attention caught by movies like The Ring and The Others which unravel their dark secrets in interesting new ways, then you'll certainly find the premise of this film interesting. A man inexplicably awakes in a pit filled with dead bodies, without memory of who he is nor any understanding of the world in which he finds himself.
But despite how immediately compelling some of Open Grave's ideas are, it is pretty shaky in its revelations and altogether confusing in many aspects.
Stylistically, the film is incredibly powerful. Through the lens of cinematographer José David Montero, Open Grave's grim world is well captured, and intense moments are made more interesting through fantastic shifts in perspective. I haven't seen any of Gonzalo López-Gallego's other films, but Open Grave clearly demonstrates his competencies in bringing a unified vision to life. But unfortunately, whether due to budget limitations or a script penned by relative newcomers to the industry, the film does not consistently engage.
Sharlto Copely continues his rather sterling record of roles and, as the only actor name on the marquee, is expected to carry the majority of the weight in this film - and he does. Sharlto is one of the few actors who consistently lives up to my expectations, and is able to elevate any production he takes part in. While his character isn't really all that deep, it's Copely that imbues him with nuance and finds a way to create a truly compelling protagonist.
But the rest of the cast is a mixed bag of mediocre and decent performances, and while it's not all on their shoulders - there's some truly weak bits of monologue exposition that really show the holes in the script - there's still much to be desired from these supporting roles. Thomas Kretschmann plays the one stand-out supporting character, Lukas, in which a significant amount of physical acting is demanded, and Kretschmann does a fantastic job of making Lukas' presence felt as much as heard.
It seems obvious that Open Grave is built around a fairly small-in-scope premise, then expanded in scope to create a story that wants to be worth watching. And it is, but it's not an experience that you're going to get lost in. Its world feels restrained and, altogether, the film doesn't feel like a brave attempt at conveying something original, when it easily could have been. Despite the technical strengths and some compelling moments, a weak script and some lackluster performances prevent this film from being fully engaging.