The director of the train company and friend of Poirot, who accompanies him and offers his own theories during the investigation.

The doctor who examines the murder victim, providing medical insight and collaborating with Poirot on the case.

A wealthy American traveling on the train, whose murder becomes the central mystery for Poirot to solve.

An energetic American traveler with her own agenda, who plays an important role in the unfolding events.

A poised and elegant passenger traveling under a false name, connected to the mystery with her own secrets to conceal.

The husband of Countess Andrenyi, a supportive figure who assists in maintaining his wife's disguise and story.

A composed and self-assured passenger whose overheard conversation raises suspicions about her possible involvement in the case.

A dignified and honorable British officer whose close ties to another passenger attract Poirot's attention.

A distinguished and aristocratic traveler with a personal connection to the case history, offering insight into past events.

A personable young man working as Mr. Ratchett’s secretary, whose background ties directly to the murder victim's past.

A devout and gentle woman, taking on the role of a nurse, whose past in the Armstrong household becomes a point of interest.

A German maid traveling with Princess Dragomiroff, whose previous service history is relevant to the investigation.

The train conductor, who diligently performs his duties amidst the turmoil and has personal ties to the greater narrative.

A brash American traveler posing as a security professional, with motivations that extend beyond initial appearances.

Mr. Ratchett’s reserved and efficient valet, performing his duties with precision and holding a background linked to the past.

A lively Italian sales representative whose past employment connects him to pivotal events preceding the current mystery.