Henry Scobie is a plain, somewhat melancholic colonial police officer serving in British West Africa during World War II. He is a Catholic convert who deeply values peace and solitude but suffers from a suffocating sense of pity and responsibility toward others. Having served for fifteen years, he faces stagnation in his career after being passed over for the Commissionership. He feels personally responsible for his wife's misery in the colonial setting.

Louise is a devout Catholic who struggles with extreme social isolation and unhappiness in the West African colony. Dubbed "literary Louise" by others, she possesses a genuine passion for poetry and literature that distances her from the expatriate community. She is heavily dependent on her husband but remains sharply observant of the people around her, dreaming of escaping to South Africa.

Wilson is a newly arrived British counterintelligence agent operating under the cover of a United Africa Company accountant. Beneath his diffident and insecure exterior, he is a romantic idealist who secretly writes and reads poetry. He quickly develops an intense, unrequited infatuation with Louise Scobie after bonding with her over literature.

Father Rank is a gregarious and slightly eccentric Catholic priest serving the colonial community. He possesses an ironic reputation as a town gossip despite his confessional duties, claiming his head is a "hive of rumours." Beneath his boisterous and loquacious exterior, he maintains a deep, perceptive understanding of human suffering and spiritual doubt.

Helen is a nineteen-year-old widow who arrives in the colony after a devastating maritime disaster. She clutches a stamp album from her father, representing her lost youth and sudden vulnerability. Her tragic circumstances and physical distress quickly make her a focal point for Henry Scobie's overwhelming sense of pity.

Yusef is a cunning and influential Syrian merchant deeply involved in the colony's black market. He operates with a cheerful but amoral approach to business, maintaining complex webs of debt and influence over local officials. He expresses a strange, persistent desire to form a genuine friendship with Henry Scobie.

Harris is a cable censor who shares a Nissen hut with Wilson. He attended the same English boarding school as Wilson and harbors a cynical view of the colony, spending his evenings inventing games to kill cockroaches to stave off his own loneliness.

Ali is Henry Scobie's deeply loyal servant who has worked for him for fifteen years. He maintains a quiet, constant presence in the Scobie household and shares a long history of enduring difficult colonial conditions alongside his employer.

Pemberton is a young assistant District Commissioner stationed in Bamba. Overwhelmed by debt owed to Yusef's store manager, he takes his own life, leaving behind a bitter suicide note to his father and sparking Henry Scobie's initial crisis of faith regarding divine mercy.

Tallit is a Syrian merchant and the primary business rival of Yusef. He operates with slightly more reputable standing than his competitor but frequently finds himself entangled in local smuggling disputes and police inspections.

The Commissioner is Henry Scobie's superior in the British colonial police force. He respects Scobie but denies him a promotion due to Scobie's tendency to attract enemies, nicknaming him "Aristides the Just."

Robinson is an eccentric bank manager in the colony. Bound by strict wartime financial policies, he coldly denies Scobie the funds necessary to secure Louise's passage to South Africa, pushing Scobie toward illegal alternatives.

Catherine is Henry and Louise Scobie's daughter who died in England several years prior to the novel's events. Her death leaves a permanent, unspoken void in her parents' marriage.

Dr. Travis is a medical professional in the colony who treats local officials. He listens to Scobie's symptoms with clinical detachment and prescribes medication, serving as an unwitting participant in Scobie's personal plans.