Paranormal Activity 4 starts off a few years after 3, with Katie living in a house with a boy named Robbie, who may or may not be Hunter, the boy she kidnapped from her sister. Robbie and Katie live across the street from the Nelson family, consisting of mom Holly, dad Doug, daughter Alex and young son around Robbie’s age, Wyatt. Almost always around at the Nelson house is Ben, would-be love interest of Alex. Webcams on computers and the Xbox 360 are how we see the action this time around, with the coolest effect going to the motion detecting power of the Kinect, which sends out a field of tiny dots to keep accurate track of movements, and which are invisible unless you’re using night vision. The tracking dots even pick up some things that the rest of the household can’t see. Paranormal, probably evil things.