Paramount Pictures’ Paranormal Activity is the ultra-low-budget horror franchise that could, with the first two films bringing in about $370 million worldwide on a combined budget of less than $4 million. So it was a no-brainer when studio heads gave the green light to a third installment, this year’s Paranormal Activity 3.

Now an official teaser trailer has been released for the third Paranormal Activity flick, answering the question: Where can this “found footage” franchise take us that we haven’t already been before?

The answer, as it turns out, is back in time. Similar to how Paranormal Activity 2 ended up being by and large a prequel to the events of the first film, PA 3 delves even further into the past. Specifically, back to the year 1988, when VHS camcorders were all the rage and sisters Katie and Kristi were just little girls who had yet to learn about the dangers of taunting malicious supernatural beings.

Catfish helmers Henry Joost and Ariel Schulman are calling the shots on the third Paranormal Activity movie, which was scripted by PA 2 writer Christopher Landon. The directing team looks to imitate the approach of the second installment in the supernatural horror series by splicing together different bits of (fake) home video footage in order to tell the story this time around – once again, a slight upgrade from the single camera approach of the first film.

It was established in the second Paranormal Activity pic that adult Katie (Katie Featherston) and Kristi (Sprague Grayden) had in fact been tormented by a mysterious demon when they were children, but had blocked out the memory of said supernatural event. So, rather than attempting to chronicle what happened in the aftermath of its predecessors, PA 3 aims to further explore and expand upon that aspect of the franchise mythos.

For more, check out the Paranormal Activity 3 teaser trailer below:

Horror prequels are often a tricky proposition and Paranormal Activity 3 seems like no exception. We already know the fate of certain characters (specifically, Katie and Kristi), so there will naturally be less tension and suspense during any scene that involves them being endangered or threatened. Plus, it’s hard to say whether or not the previous Paranormal Activity films really suggested that there was a whole lot more that needed to be said about the events that led up to them (this fall’s The Thing prequel is in the same boat, for that reason).

Can PA 3 throw us some curveballs and reveal that there’s much more to Katie and Kristi’s backstory than we were previously led to believe? We’ll just have to wait and see, for now.

Paranormal Activity 3 arrives in U.S. theaters on October 21st, 2011.