The people who wanted an explanation would ruin what this movie is.

Who knows what Martin is? Who knows how he's doing what he's doing? I don't and that's the power of this film. That's the horror of this film.

There's no rational explanation and none is needed. It's so much better without it and it is the movie it is because of its lack of explanation.

People say "Oh it would have been better if we found out Martin was poisoning them." Really? A movie about a kid poisoning a family to get revenge for his father's death? That's it? A nice neat bow? That would have made this movie better in your eyes? Respectfully, I absolutely disagree.

This is a film set in a strange world occupied by strange people. Some of these people are so strange they defy even the logic of this macabre reality.

What is Martin? I don't know and never want to. What is the force in "It Follows"? I don't care because its mystery is all the greater and terrifying for it. Whether the recently announced sequel explains this I don't know and I bet the filmmakers knows this too and we'll be left with more questions than answers and, again, that's fine with me. The unknowable. The truly alien. That's true horror. That which our minds cannot create any logical connections to the events unfolding.

"I'm really sorry about Bob."
"It's nothing serious."
"No it is."

Chilling. I love it and let's leave it at that.