Insidious 2 was pretty, pretty bad. Yet, somehow, it made an absolute truckload of money.

So much so, that here we are with a totally unnecessary prequel. Just to put this in perspective, here's some numbers for just how profitable Insidious has been.

The first one was made for $1.5 million. How much did it make? $97 MILLION.

The second one? Made for $5 million. It cleared $167 MILLION.

These films are basically a licence to print money and we really have no idea why. The previous two were both AWFUL, but hey - we're not knocking it.

If people dig crappy horror films and are willing to throw money after it, then people will keep making them.

The third Insidious film, which is a prequel because d'uh, sees Dermot Mulroney - who we honestly thought was better than this - playing a young father with a daughter that looks suspiciously like Chloe Moretz.

As you'd expect, the daughter is being haunted by her dead mother and a psychic has to get involved to save her.

If we eye-roll any harder, our retinas will become detached.

Watch the trailer and think about how much money this is going to make.