The two sisters, Beth and Sara, begin their documentary project on spiritual mediums in hopes of finding some answers about the afterlife and connecting with their deceased parents. They visit a few well-known mediums but are disappointed with the results, as they all seem to be fake and only in it for the money. However, they eventually meet Mike, who they believe to be a genuine medium, and they begin filming with him.
As they start filming, Mike tells them about a disturbing mystery he has been trying to solve for years. He believes that Sara's fiancé, Lucas, who was presumed dead after a car accident, might actually still be alive. Mike has been receiving messages from Lucas through his medium abilities and is convinced that he is being held against his will at his childhood home.
Sara, who was devastated by Lucas's death, is initially skeptical but becomes more and more convinced that Lucas could still be alive as Mike reveals more details about the messages he has received. Beth and Sara decide to investigate and travel to Lucas's childhood home to uncover the truth.
As they arrive at the abandoned house, they begin to experience strange and terrifying occurrences. Shadows move on their own, doors open and close on their own, and they start hearing Lucas's voice. As they get closer to the truth about what happened to him, they realize that the danger they are facing might be more than they bargained for.
Dead Voices is a suspenseful horror movie that keeps viewers on the edge of their seats as the sisters race against time to uncover the truth and save Lucas from whatever is holding him captive.