The enduring horror franchise about haunted houses in suburban America returns with "Paranormal Activity 4," which means more creaking doors and bumps in the night. The shtick has been wearing thin, but this time the filmmakers add something new: a pretty, blond teenage heroine.

About time! To its credit, "Paranormal Activity 4" almost never ogles young Alex, played by appealing newcomer Kathryn Newton, but she and her almost-boyfriend Ben (a likable Matt Shively) bring a youthful energy to this ossifying series. They're an endearing pair, flirting and sharing confidences via Skype. When Alex gets up from her bed to inspect the latest thud downstairs, a lovelorn Ben cries out from her laptop screen: "Wait, take me with you!"

The story follows a little boy, Robbie (Brady Allen), who comes to stay with Alex's family and triggers a series of strange events. When Alex grows suspicious, Ben reassuringly sets up computer cameras everywhere, providing us with the found-footage experience these movies are known for.

The scares are hit-and-miss, but at least Alex and Ben are fun to hang out with.