In the anatomy of a crime, the loudest confessions are often silent. They hide in the quiet grain of paper, waiting for the right light. Before dawn, a technician holds a letter. The air bites with solvent as, under an angled lamp, a watermark blooms—the faint crest of a distant paper mill. A pale sorting smudge on the envelope points not to the city the letter claimed, but to a regional hub. T...
