Our method

Mystery Dossier is published by FIRMIO SAS (France). Our dossiers are designed by a small editorial team, assisted by artificial-intelligence tools for research, first drafts, layout and illustrations (generated illustrations, no real person, no text).

Every piece of information carries a label: FACT (recognised source), TESTIMONY (what someone stated), RUMOUR (unproven), GAME (invented for the puzzle). Fictional characters are always flagged and never attribute wrongdoing to a real person.

Checking: facts are cross-checked against primary sources (official reports, archives, period press) and historians' work; when sources disagree, we say so. Puzzle solutions are proven unique by software. Uncertain points are listed for review by a historian.

Respect: we describe no violence, we tell the victims' stories through their lives, and we never name a real suspect as guilty without established proof.

Spotted an error? Write to contact@mysterydossier.com: every report is checked and the page's last-checked date is updated.

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