Plot holes and explanations
So there has been a few questions that have arisen in terms of why something happened in the story, and I thought I would just explain those here. A lot of the explanations are not clearly written out in the script because I didn't want it to be spelled out so plainly, so it's not like anyone was missing something as they watched. Spoilers obviously:
1. The infected follow Abira because she is infected, they are drawn to her as if they can smell her (talked about in the movie) They are drawn to each other by smell, and are also attracted to people by the same means. Abira smells like both, uninfected and infected, which would trigger in them a frenzy. If infected and uninfected are in the same place at the same time it means that it's time to feed. That's why they are drawn to her so strongly.
2. The infected don't attack Penelope and instead follow Abira to her death. This goes back to the smell, not only is her scent more appealing that Pen's but also Pen accidentally, but effectively masks her smell with the lighter fluid. She intends to set herself on fire, but essentially makes herself invisible to the infected. She chalks it up to being lucky, and a mini-miracle.
3. The infected do eat one another if blood is spilled, as shown when our survivors kill an infected trying to come into where they were staying that night. They are opportunistic and will go for the weak in their pack if they've been injured.
4. Why do Pen and Josh keep having sex? Because that's what people do, they are young, and in love and there's no such thing as birth control anymore. Them never having sex would be odder than them having sex with the possibility of a miscarriage. That's how I feel though.
5. Pen's inability to read, or difficulty with it comes straight from my own childhood. There was no reason I had trouble reading as a little kid...I just couldn't do it well. With some individualized attention from an expert I ended up doing great. These characters exist in a world where they are no schools, everyone is on the run, and children are sheltered, her parents had more important things to worry about than giving their kids a well rounded education. Other children like Josh were given better opportunities, I wrote a series of short stories from the world of Chrysalis such as this one: http://therestaredead.tumblr.com/post/83230257940/not-lusus-naturae-we-called-them-silents-no-one
It explains Josh's education as a child, one that Pen didn't receive. If you enjoyed that story and want to read more they are all on that Tumblr site. Pen hides her inability from people for the same reason people who can't read today hide it from the world. It's an embarrassment for them.
6. Pen having shaved arm-pits. You got us there, it was an oversight and a funny one at that.
7. Pen pregnant at the end, yes, it is physically impossible for her to be pregnant within a few weeks of her miscarriage, this was intentional, it's meant to be a miracle. Not immaculate, it's Josh's.
If there are other holes that people find that they might have a question about please feel free to ask me. Thank you to everyone who watched it. If you loved it, great! If you didn't then we hope to make a movie you'll like next time. As I said before none of these plot holes are explicitly explained. As the writer I don't like to write explanations into my scripts, but as I see that it bothers people I will be more careful next time. Thanks again for watching.