A garota que assassinou no começo do filme é a namorada de Hugh. Os protagonistas encontram uma foto de Hugh e sua namorada. Ambos, Hugh e sua namorada, são perseguidos por ela. Hugh conhece as "regras" da criatura em It Follows, porque ele as aprende com a sobrevivência.
Em uma nova entrevista com o Yahoo! :
You’ve said in other interviews that you didn’t set down concrete rules in terms of what the monster can or can’t do. But we do hear some rules in the film.
The only rules that we hear are rules that we’re told by a character within the film, who has access to limited information. If you look at the film enough, you can start to understand how he may be figuring these things out and how he has gotten the information that he has. But you also have to understand that they’re not rules on a stone’s tablet; they’re a character’s best guess about what’s happening to them. So, you know, they seem mostly right. But for me, that’s kind of fun, in that there might be some gaps in information, some things that he doesn’t understand and neither do we.
Ele realmente entra no meio disso durante um reddit AMA . Um leitor perguntou como o personagem de Hugh em It Follows sabe muito sobre a origem da maldição da infecção.
Hiphopsanta: "I'm sorry but I need to ask this spoiler question: in It Follows, how does Hugh know how to beat the monster or even discover that at all, if no one ever explained it to him? He said he "thinks" he got it from a girl a bar, but wouldn't he know for sure? How would he even know it came from sex?"
David Robert Mitchell: "This suggests a much larger backstory within Hugh's life. We can only imagine the circumstances that led to Hugh discovering this. The film offers a few clues".
Mitchell continua revelando mais sobre sua percepção de "Isso":
“For one, looking like normal people, it has the ability to approach the character without them being aware that it’s the monster. Also, it’s the way that the monster uses the human figure to hurt or disturb the characters.”
“I think most of the time It’s always walking,” “But It can choose to move in ways that might hurt or affect the person it’s
following.”“It could certainly cross the ocean. I imagine that it could get on a boat or a plane. Or it could move through the water, if it chose to.”