A bookish boy a little older than twelve, Klaus uses his extensive knowledge to navigate the dangers he and his siblings face. He is recognized for wearing glasses and frequently delves into books for solutions.

An infant small for her age with a habit of biting, Sunny often communicates in shrieks that somehow fit the situation. Her sharp teeth become significant in their adventures.

The primary antagonist, a distant relative of the Baudelaire children, Count Olaf is tall, thin, and menacing, distinguished by his single eyebrow and intent to seize the Baudelaire fortune.

A banker and executor of the Baudelaire estate, Mr. Poe acts with bureaucratic precision but inadvertently contributes to the children's misfortunes with his adherence to rules.

Count Olaf’s neighbor and a judge, Justice Strauss offers a glimpse of kindness and legal insight to the children. Her home and library provide them temporary refuge.

Members of Count Olaf’s theatrical troupe who assist in his schemes, often characterized by distinct physical traits and a surreal presence that adds to Olaf’s intimidating power.

The narrator of the story who provides a whimsical, sardonic commentary on the Baudelaire’s misfortunes. He frames the narrative and sets the tone of the series.