The Circumference of the World - Lavie Tidhar

Delia Welegtabit discovered two things during her childhood on a South Pacific island: her love for mathematics and a novel that isn't supposed to exist. But the elusive book proves unexpectedly dangerous. Oskar Lens, a science fiction-obsessed mobster in the midst of an existential crisis, will stop at nothing to find the novel. After Delia's husband Levi goes missing, she seeks help from Daniel Chase, a young, face-blind book dealer. The infamous novel Lode Stars was written by the infamous Eugene Charles Hartley: legendary pulp science-fiction writer and founder of the Church of the All-Seeing Eyes. In Hartley's novel, a doppelganger of Delia searches for her missing father in a strange star system. But is any of Lode Stars real? Was Hartley a cynical conman on a quest for wealth and immortality, creating a religion he did not believe in? Or was he a visionary who truly discovered the secrets of the universe?