The Void is a horror movie in the style of HP Lovecraft. The first act does a good job at building tension and keeping you guessing as to what’s going on. Unfortunately, despite some reasonable practical effects that a reminiscent of The Thing, the low budget and poor cinematography take their toll. As well, the writing gets weaker and the demands placed by it’s weak explanation of what is going on stretched my ability to suspend disbelief.
The acting is passable, especially considering the cast of relatively unknown actors. Unfortunately, what started out as a promising disturbing tale devolved into a badly lit low budget monster film. Veteran actor Kenneth Welsh fails to sell his character, who is the lynch pin on which the story turns, though he need not shoulder all of the blame; he did a creditable job with what the script gave him.
While still flawed, the film The Mist, based on the story by Steven King, does a much better job of capturing the horror of the world of the elder gods touching our own. More recently, Stranger Things nailed the material. The Void explores the idea of a cult (rather than science) being the instrument of the dimensional breach, but fails to do so convincingly. The idea is more adequately explored by Lovecraft himself.