The newest installment follows a teenage girl named Alex, whose new neighbors just happen to be Katie and a little five-year-old named Robbie (who looks remarkably similar to the still-missing Hunter). Not surprisingly, some strange things start happening in the neighborhood, and it only gets worse for Alex's family when she needs to babysit Robbie.
To get caught up on the full "Paranormal Activity" story, check out the exclusive clip up at the top detailing the family history of Katie and Kristi. It even offers a sneak preview of what to expect next, so if you need to brace your nerves for opening night, you better get started now.
"Paranormal Activity 4" hits theaters on Friday, October 19.