Sydney Wells (Jessica Alba) is blind and has been so since a childhood tragedy. After undergoing surgery to restore her sight she learns to see again. But soon after, unexplainable shadowy and frightening images start to haunt her. Not knowing if they are an aftermath of surgery, her mind adjusting to sight, her imagination, or something horrifyingly real, Sydney is soon convinced that her anonymous eye donor has somehow opened the door to a terrifying world only she can now see.