Ian Lindsey’s review published on Letterboxd:
Technically this is based on the comic book series of the same name. However, the adaptation is so loose that I wouldn't be surprised if director/writer David Prior had some of the ideas and images here already kicking around before getting attached to this project. This very much has the feeling of a long gestating debut and does have some of the overstuffing that so often comes with those kinds of movies.
Empty Man feels like a mashup between two of the main trends in horror right now: the slick Blumhouse jumpscare engine and the artsier mumblegore/elevated horror/whatever. It also adds in more than a little of Fincher's style which isn't all that surprising considering how many making of docs that Prior has made about Fincher movies.
This is longer than it needs to be. It also loses momentum somewhere in the middle and never fully recovers. Still, the parts that are good (the twenty minute prologue, Stephen Root, the entire training camp sequence) are very good. It's also nice seeing something that takes the Lovecraft influence into unknowable, cosmic dread instead of just tentacles.