Here is why movie Paranormal Activity scared me as much as it did. It had nothing to do with demons or ghosts.

It tapped into the most primal of fears. You wake up with a start in the middle of the night convinced that someone is in your house.

It used to happen to me as a kid. I’d wake up convince there was someone in the bedroom. I could almost make out their shadow in the room. I could imagine them crouching in the dark. I would lie frozen in bed, convinced that any sign I gave of life would be the end of me. Sometimes if I was lucky I’d drift back to sleep. Sometimes I would have to wait until the first gray light of dawn seeped through the curtains and make me realize there was no one in there, just my clutter. I could have called out to my parents. Or my sister. I could have turned on the flashlight. But instead all I knew to do was lie still and hope whoever it was didn’t realize I was awake.

If I needed to go to the bathroom, I’d just lie in bed clenching my bladder. The bathroom required running across two dark hallways and then turning on the light. And who knew who lurked out there.

Of course, there was nothing a self respecting robber would want from my room. Scores of Enid Blyton adventure stories (some of which probably had something to do with the intruder-in-the-dark nightmares anyway), a globe, school books and endless little craft projects – none of them worth much on the black market. But thieves were not so picky in our neighborhood in Calcutta. Once someone broke into the house next door. All the doors to the rooms were locked. So they just stole all the slippers and shoes neatly lined up outside the door.

Paranormal Activity was about that fear. There is someone in the house. What was worse was we saw the couple asleep in bed but knew what they didn’t realize yet – there was someone in the house, and it was coming up the stairs, towards their bedroom.

It’s being called the scariest movie since Blair Witch Project. But Blair Witch didn’t scare me because as a city kid in India I had no experience going camping in the woods. That was a fear I couldn’t really tap into – the spookiness of dark woods at night. This was more like Sixth Sense on a Blair Witch budget and minus a star like Bruce Willis. So it all felt more real, unfolding as if on someone’s home movie.

In fact, these days so much of our drama unfolds on home movies and Iphones and Youtube. Whether it’s a Chinese lady and an African American woman coming to fisticuffs on the bus in San Francisco, or a Chicago teenager being beaten to death, the horrors of day to day life are immediately uploaded into our consciousness. Paranormal Activity feels like that – as if it is cobbled together from home video and a geeky tech-savvy world. The normal activity of obsessively recording everything about our lives suddenly tips over into the dark side.

“Zoom in, zoom in,” an unknown woman exhorts the person filming the beating of Derrion Albert in Chicago. Paranormal Activity zooms in and we are all watching with bated breath.

In my scaredy cat childhood once the sunlight broke through and the cacophony of the day erupted around me, the demons of the night seemed far away and ridiculous. Until night fell again, and the house settled down to sleep around me. In Paranormal Activity daytime brings no respite. There is the recording of the night which they have to go through and analyze. All the things that go bump in the night are still there saved as .wav files for your daytime listening terror. Put down the camera, the young woman tells her husband. He didn’t.

Technology was supposed to save the couple. But it sent them tumbling down the rabbit hole instead, trapping them in their nightmares.

That’s the really creepy thing about Paranormal Activity.