A good portion of whether something is watchable is not whether it has been done before (most things have been) but whether it is done well.
Don't Knock Twice does nothing that has not been done before. That said, what it does do, it does awfully well. This is a very atmospheric horror, sounds as well as visuals, play a key part in its success. As does things hinted at or glimpsed, as well as things that are seen.
The pacing is good with well timed scares occurring throughout this flick. Moreover, it manages to feel fresh and new even though its a well worn proposition. I personally put this down to decent acting and directing.
Ignore the detractors and give Don't Knock Twice a go. Seven out of ten from me.
