The Round Tower
The body of Professor Emil Brandt was discovered at 6:47 on a Monday morning by a janitor whose name would never appear in the newspapers, though it was he who would dream about the scene for years afterward. Brandt sat at his desk in the observatory atop the Round Tower as though he had simply fallen asleep over his work — head resting on crossed arms, spectacles askew, a half-drunk cup of coffee growing its own civilization beside his elbow. It was only when the janitor touched his shoulder that the stillness revealed itself as something more permanent than sleep.
Inspector Katrine Holm arrived forty minutes later, her coat damp from a rain that had been falling since October and showed no intention of stopping before spring. She noted the details with the methodical detachment that had made her reputation and ruined her marriage: no signs of forced entry, no visible wounds, no indication of struggle. The toxicology would take days, but she already suspected poison — the faint almond scent beneath the coffee's bitterness, the slight cyanotic tinge around the lips that most people would miss but that Katrine's eyes, trained on a decade of Copenhagen's dead, caught like a familiar word in a foreign sentence.
The equation was harder to explain. Carved into the surface of the oak desk with what appeared to be a compass point, it covered nearly a square meter — a dense lattice