I've reviewed every sequel in the Paranormal Activity franchise for Screen International, and I'm happy to say I'll be doing the same for this week's Paranormal Activity 4. (I'm seeing it Tuesday night.) I think this is a quite good series of horror films -- inventive and stripped-down in a way that allows for nice, solid shocks. For Deadspin, I advance the theory that this franchise has improved with each installment. Enjoy.