Darkest Light is the rare sequel that makes its predecessor feel like a prologue: it deepens and darkens the visceral fantasy begun in the Sunburst Award–winning Half World. While the tale it tells is very similar in structure to that of the earlier book, Darkest Light feels less like a retread than a successful reboot.

In the first book, we learned that the universe is composed of three realms: the Flesh, the Spirit, and the Half World, where people relive their most horrific moments until they overcome them and are free. The realms have been thrown out of whack but are realigned by the defeat of the nihilistic Mr. Glueskin, who is reborn as a human infant and smuggled into the realm of Flesh.

Darkest Light picks up the story 16 years later. The baby that was Glueskin is now a brooding, pale-skinned teenager named Gee, who has no knowledge of the three realms. After he discovers the truth, he is compelled to return to Half World, along with an unhappy lesbian friend and a talking cat. Once there, his former nature threatens to return, and the story becomes a meditation on free will, fate, and the nature of morality: if people are destined to keep returning to Half World to relive moments of utter horror no matter how good or bad they are as Flesh, why not just stay there and rule as cannibalistic monsters?

Whereas the earlier book, for all its many strengths, felt tentative and too short, Darkest Light exploits this compelling scenario for all its potential. This is a remarkably philosophical book – it is easy to see the allure of the choices made by Half World’s monstrous denizens, and difficult to imagine oneself choosing differently. It is also a violent story, full of nightmarish scenarios straight out of a Bosch painting. The violence is never gratuitous or lazy, however. Darkest Light is very smart, right up to its genuinely surprising final scene.