# Halliday — The Big Four character guide

> Halliday in The Big Four by Agatha Christie.

**Role:** minor

**Also known as:** M. Halliday, This M. Halliday, John Halliday

**First appearance:** 0000-i-the-unexpected-guest

## Who they are

A man whose death is linked to the Big Four conspiracy.

## Relationships

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

_professional_

Halliday is a character connected to the case, possibly a suspect or relative of a victim, interacting with Poirot.

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

_professional_

Halliday is a character connected to the case, possibly a suspect or relative of a victim, interacting with Poirot.

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

_professional_

Halliday is a character connected to the case, possibly a suspect or relative of a victim, interacting with Poirot.

## In the story

### [V: Disappearance of a Scientist](https://www.betterreads.dev/discover/the_big_four_se/chapters/v-disappearance-of-a-scientist)

British scientist who disappeared in Paris; his work on wireless energy is linked to the Big Four.

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

Missing English scientist; later rescued but refuses to speak about the Big Four due to fear.

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

Recently released, his nerve is broken; he departs for England.

## Links

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