As was explored in the science fiction master’s 2014 prequel, time in Agency is split in two—or really, more. The narrative occurs in both the near future and a distant one, where all of what modern society fears—climate change, pandemics, wars over resources—has slowly wiped out 80% of humanity, and those remaining possess the technology to tweak the events of different parallel “nubs” of the past, thus changing their future. (Think of a tree of timelines sprouting a new limb, often to explode into apocalypse.) Recrafted after the real-life 2016 electoral shocks in the U.K. and the U.S., William Gibson’s seductive sequel to The Peripheral is set in a nub where neither Brexit nor the Trump presidency come to pass, but in a world that is still very much in need of saving. That is, if a new, powerful A.I. will allow it.