Steph and her mother no longer need to run from her father, thanks in part to the help of Steph’s online friends from CatNet and the Artificial Intelligence (AI) that runs CatNet, who calls themself CheshireCat. Now Steph is living in Minneapolis and registering for a private school that’s designed for students who may have gaps in their education.

On her first day at the new school. Steph meets Nell, who had been homeschooled by her mother. But over winter break, Nell’s mother had gone missing, so now she’s staying with her father. Nell’s mother had been very religious, in a group that may have been a cult. Then the police found her car and nothing else. There had been no sign of her. Nell doesn’t think that her mother would just leave her and stage her own disappearance, but there is nothing she can do to find her.

As Nell and Steph sit talking about their unusual backgrounds, another student comes over and asks them if they know about the Mischief Elf app. and when they say no, she gets them to add it, so she can get rewarded for getting new members into the group. It’s an app that asks you to do things, and the more of the tasks you complete, the more you get rewards. Nell notes that it seems similar to another app she uses calls Catacombs, which has the same format but is religious based.

Steph is excited to have a real friend who lives close by (her girlfriend is a couple of hours away), so she signs into the new app (under a pseudonym—she’s smart about internet security)—but she finds some of the tasks to be questionable. Some are fine, innocuous tasks, but others could have unwanted consequences—like, when someone is asked to cross the street against the light or steal a tool from a hardware store.

But then Nell’s best friend—girlfriend—goes missing, it’s up to Steph, Nell, and CheshireCat to try to figure out where she might have gone. And as they try to find her, they get the feeling that there is something more happening to them. Maybe it’s not a coincidence that the Mischief Elf app and the Catacombs app look so much alike. Maybe they’re related to each other, and to Nell’s mother’s religious doomsday cult. But for that to be true, for someone to be able to synthesize all that information together, there would have to be a very intelligent human behind it all. Or another Artificial Intelligence, like CheshireCat,.

But how many programmers out there are smart enough to create another AI? And what could their intentions be with it? As Steph and Cheshire get closer to finding out, the danger around them rises. There are riots and fires, bombs and people spilling into the streets ready to fight each other. Could it be the Tribulation that the cult has been prepping for, or is the AI using them to burn humanity to the ground for a deeper purpose?

Chaos on CatNet is the follow-up to Catfishing on CatNet, and not only does it continue the story started in the first book, it expands the danger from Steph and her mother to entire cities of people. Although you don’t have to read the first book to understand this one, I recommend that you do, just because it’s a very good book. Author Naomi Kritzer has taken the future she started in Catfishing and applied it to society, weaving in subversive questions of what makes us human and if programming can be changed once it’s set.

I loved Catfishing on CatNet and was so excited to find out that there was a sequel. I was a little apprehensive reading Chaos on CatNet, because there’s always the worry that the next book in the series won’t be as good. But I think Chaos was even better. Introducing the religious cults and unusual families added personality and danger to the story, and Steph herself was smarter and more confident in very impressive ways. I did have the urge to wipe all apps from my phone, but other than that, reading Chaos on CatNet made my week. I highly recommend both CatNet books. I mean, what else is the internet for, if not cat pictures (and book reviews)?

Egalleys for Chaos on CatNet were provided by Tor Teen (Macmillan) through NetGalley, with many thanks.