# Monsieur de Marquet — The Mystery of the Yellow Room character guide

> Monsieur de Marquet in The Mystery of the Yellow Room by Gaston Leroux.

**Role:** supporting

**First appearance:** 0009-viii-the-examining-magistrate-questions-mademoiselle-stangerson

## Snapshot

An examining magistrate who treats the law as theatre, dreading nothing more than a mystery's explanatory final act.

## Who they are

Monsieur de Marquet presides over the inquiry into the Yellow Room affair, but his true passion is the stage—he writes plays under the name 'Castigat Ridendo' and savors cases that furnish him with drama. He throws himself into the investigation less as a truth-seeker than as an amateur of intrigue, and he begs his registrar that the builder's pickaxe not destroy so fine a mystery. His theatrical temperament shapes the early investigation's tone, making him both an obstacle and an ornament to the pursuit of fact.

## In the story

### [In Which We Begin Not to Understand](https://www.betterreads.dev/discover/the_mystery_of_the_yellow_room_se/chapters/i-in-which-we-begin-not-to-understand)

The examining magistrate from Corbeil, who describes the case as baffling and notes the impossibility of the assassin's escape.

### [In Which Frédéric Larsan Explains How the Murderer Was Able to Get Out of The Yellow Room](https://www.betterreads.dev/discover/the_mystery_of_the_yellow_room_se/chapters/xi-in-which-fr-d-ric-larsan-explains-how-the-murderer-was-able-to-get-out-of-the-yellow-room)

Examining magistrate who orchestrates the informal discussion and expresses frustration at the case.

### [Rouletabille Knows the Two Halves of the Murderer](https://www.betterreads.dev/discover/the_mystery_of_the_yellow_room_se/chapters/xxiv-rouletabille-knows-the-two-halves-of-the-murderer)

Presides over the questioning and arrest of Darzac, visibly moved by the scene.

## Links

- HTML: https://www.betterreads.dev/discover/the_mystery_of_the_yellow_room_se/characters/monsieur_de_marquet
- Book: https://www.betterreads.dev/discover/the_mystery_of_the_yellow_room_se
- All characters: https://www.betterreads.dev/discover/the_mystery_of_the_yellow_room_se/characters