The Big Four · Chapter
The Woman on the Stairs explained
Poirot and Hastings travel to Paris to investigate the disappearance of John Halliday.
What happens
Poirot and Hastings travel to Paris to investigate the disappearance of John Halliday. They interview Professor Bourgoneau and Madame Olivier, who confirms Halliday discussed his scientific work with her. Poirot notices a woman in mourning who enters the villa and runs upstairs without looking at them, finding her behavior suspicious. After a near-fatal accident with a falling tree, Poirot deduces that Halliday was likely kidnapped by the Big Four, possibly impersonated by Number Four, and that the woman on the stairs may have been involved. Halliday is later rescued from a villa by the Countess Rossakoff, but refuses to speak about his ordeal, fearing reprisals against his family.
Themes in this chapter
Global Criminal Conspiracy
The Big Four orchestrate Halliday's kidnapping and threaten his family, demonstrating their far-reaching power.
Intelligence and Deduction
Poirot uses observation and reasoning to deduce the woman on the stairs's unnatural behavior and the likely impersonation of Halliday.
Characters to notice
- Hercule Poirot
Leads the investigation into Halliday's disappearance in Paris, interviews Madame Olivier, and deduces the involvement of the Big Four.
- Captain Hastings
Accompanies Poirot to Paris, observes the woman on the stairs, and is nearly killed by a falling tree.
- Madame Olivier
Famous scientist interviewed by Poirot; confirms Halliday discussed his work with her in her laboratory.
- Halliday
Missing English scientist; later rescued but refuses to speak about the Big Four due to fear.
- Countess Vera Rossakoff
Assists in rescuing Halliday from a villa; leaves a note signed 'I. V.' which Poirot finds suspicious.
Key passages
“This Big Four, they make me to bestir myself, mon ami. I run up and down, all over the ground, like our old friend 'the human foxhound.'”
Poirot jokes that the Big Four are forcing him to be as active as a detective he once knew.
Poirot compares his frantic investigation to the energetic detective Giraud.
“A woman who enters her home—for I presume that it is her home since she enters with a key—and runs straight upstairs without even looking at two strange visitors in the hall to see who they are, is a very unusual type of woman—quite unnatural, in fact.”
Poirot finds it suspicious that a woman would enter her house with a key and ignore two strangers in the hall.
Poirot's observation of the woman on the stairs leads him to suspect her involvement.
“If I remain silent, I shall be safe—if I say one word—not only I, but my nearest and dearest will suffer unspeakable things.”
Halliday refuses to talk because he fears the Big Four will harm his family if he speaks.
Halliday's terror shows the Big Four's power to intimidate even after rescue.