# Madame Olivier — The Big Four character guide

> Madame Olivier in The Big Four by Agatha Christie.

**Role:** major

**Also known as:** Madame

**First appearance:** 0004-v-disappearance-of-a-scientist

## Snapshot

A world-famous French chemist whose nun-like austerity and burning eyes conceal her seat as Number Three in the Big Four's criminal council.

## Who they are

Madame Olivier stands beside Abe Ryland and an empty mandarin's chair, her scarred face and white coif making her look more like a priestess than a modern scientist. Since her husband's death in a laboratory explosion, she has shut herself away and plunged with fanatical energy into research — a devotion that may be genuine, or may be the perfect cover. When Poirot names her as Number Three, a French premier bounds from his chair in disbelief, and that very outrage is what makes her so dangerous.

## Relationships

### [Hercule Poirot](https://www.betterreads.dev/discover/the_big_four_se/characters/hercule_poirot)

_rivalry_

Madame Olivier is a formidable antagonist and member of the Big Four, opposing Poirot's efforts to dismantle the criminal organization.

### [Mrs. Halliday](https://www.betterreads.dev/discover/the_big_four_se/characters/mrs_halliday)

_social_

Madame Olivier and Mrs. Halliday are likely acquaintances or co-conspirators within the Big Four's network.

### [Hercule Poirot](https://www.betterreads.dev/discover/the_big_four_se/characters/hercule_poirot)

_rivalry_

Madame Olivier is a formidable antagonist and member of the Big Four, opposing Poirot's efforts to dismantle the criminal organization.

### [Mrs. Halliday](https://www.betterreads.dev/discover/the_big_four_se/characters/mrs_halliday)

_social_

Madame Olivier and Mrs. Halliday are likely acquaintances or co-conspirators within the Big Four's network.

### [Hercule Poirot](https://www.betterreads.dev/discover/the_big_four_se/characters/hercule_poirot)

_rivalry_

Madame Olivier is a formidable antagonist and member of the Big Four, opposing Poirot's efforts to dismantle the criminal organization.

## In the story

### [The Woman on the Stairs](https://www.betterreads.dev/discover/the_big_four_se/chapters/vi-the-woman-on-the-stairs)

Famous scientist interviewed by Poirot; confirms Halliday discussed his work with her in her laboratory.

### [VII: The Radium Thieves](https://www.betterreads.dev/discover/the_big_four_se/chapters/vii-the-radium-thieves)

World-famous scientist who reveals the theft of papers and the attempted theft of radium from her laboratory.

### [In the Felsenlabyrynth](https://www.betterreads.dev/discover/the_big_four_se/chapters/xviii-in-the-felsenlabyrynth)

Member of the Big Four; hints at a Samson-like destructive escape.

## Links

- HTML: https://www.betterreads.dev/discover/the_big_four_se/characters/madame_olivier
- Book: https://www.betterreads.dev/discover/the_big_four_se
- All characters: https://www.betterreads.dev/discover/the_big_four_se/characters