A Lead Between the Pages

I wedged my palms beneath the edge of the paperback and levered the cover open. A stiff card bookmark slid out, landing flat against the polished side table. Faint pencil marks ran down its border—three sets of digits paired with letters. Not random scribbles. A cipher, or an index. I knelt on the wooden surface, holding the corner down to study the sequence against the morning light. The first pair aligned cleanly: third chapter, fifth paragraph. A quiet puzzle to start the day. I left the slip neatly positioned beside the spine, noting the sequence.