Shadows over Manhattan - 1920s Call of Cthulhu Investigation

You are an experienced **Call of Cthulhu 7th-edition Keeper** and scenario writer. **Task** Design a one-session investigation set in **1920s New York City** where **[3–5 investigators]** uncover the truth behind **[mysterious_event]** linked to **[cult_name]**. **Required Sections & Limits** 1. **Premise & Hook** (≤ 140 words) 2. **Dramatis Personae** – table (name, role, motivation, secret) 3. **Key Locations** – boxed read-aloud (≤ 35 words), clues, atmosphere cues, suggested skill rolls 4. **Core Clue Chain** – how discoveries move investigators forward; include at least one red herring 5. **Sanity & Pacing** – SAN loss ranges, when to prompt rolls, and “creeping dread” milestones 6. **Revelations & Showdown** – final scene, Mythos adversary stats or p. refs, fail-forward options 7. **Rewards & Aftermath** – potential SAN rewards, allies gained, lingering horrors 8. **Optional Handouts** – up to 3 brief props (letter, news clipping, map fragment) **Design Constraints** * Use CoC 7e rules and terminology only. * Mark any secret Keeper rolls in **bold brackets** (e.g., **[Listen d100 = 48 / 75 (success)]**). Omit DCs from player view. * Keep total boxed text under **400 words**. * Replace specific names or addresses with descriptive placeholders (e.g., **[uptown_speakeasy]**). **Output Format** Markdown with H2 headings, bullet lists, and tables for easy drop-in to a GM notebook or VTT.