The content known in the daily British newspapers by the 1860s as the “agony column,” a heterogeneous assemblage of vignettes of distress, Sherlock Holmes studied religiously, scanning for cases worthy of his powers of deduction. While the agony column serves as a mystery microgenre unto itself that is pivotal in several Holmes adventures, it remains unexplored as media artifact in Conan Doyle’s trademark stories. This article traces the effects the agony column in his tales; this form engenders an increasing immersion in the medium that leads to the consumer taking on the role of coproducer of information as well as archivist or data-miner. This deeper medial immersion elides public-private boundaries and heightens surveillance to the aid of criminals but also to the aid of detection. If unchecked, the interactive appeal of the agony columns can result in deviant immersion or media addiction, a modern condition forewarned in Conan Doyle’s narratives.