The Sapphire of Saint-Cloud

Locked room. Watched door. Vanished sapphire. Impossible crime.

Era

Paris, autumn 1925

Difficulty

Medium

Playtime

1h 30m

Rating

New

The Villa de Saint-Cloud presents an impossible puzzle: a locked drawing room, a valet who never left his post, yet a stolen sapphire and a dead heiress. The evidence contradicts itself. The suspects all lie. Logic is your only weapon.

Content advisory

Recommended 16+

Contains: depiction of homicide and crime-scene description.

Fictional case file · AI-generated and editorially reviewed

What is in the envelope

20–30 evidence documents

Police reports, witness statements, autopsy notes.

Period correspondence

Letters, telegrams, handwritten notes.

Pen-and-ink illustrations

Mugshots, crime scenes, evidence shots — period-appropriate.

5+ suspects

Each with motives, alibis, and red herrings.

A definitive solution

Sealed at the back — read only when you are ready.

What you will be solving

The facts are these: Margaux Vallin enters a locked drawing room at half past midnight. Her valet stands guard in the corridor—he does not move, does not sleep, does not see a single guest pass. At two in the morning, Margaux is found dead in the orangery. The sapphire is gone. The valet's testimony is ironclad. The room's windows are sealed from the inside. The door was locked. Yet the evidence at the scene tells a different story. Six guests remain at the villa, each with a fabricated name and a fractured alibi. Their timelines overlap in impossible ways. Their stories contradict. Someone is hiding something. This is a puzzle locked inside a locked room. The sapphire's disappearance and Margaux's death are connected—but not in the way the initial investigation assumed. The solution lies in the careful reconstruction of the night: who was where, who had access, and how a crime could occur in a space that was supposedly under constant watch. Examine the evidence. Cross-reference the testimonies. Find the flaw in the impossible.