The Leech Woman

An accomplished endocrinologist who becomes entangled with Malla's quest for youth, funding her trip and enabling dangerous experimentation. His ambition blinds him to the human cost, showing a willingness to manipulate others for a scientific 'breakthrough'.

Paul's wife, an alcoholic who resents the marriage and schemes to turn youth into a tool for revenge. She disguises herself during the Africa trip and later masquerades as her own niece to pursue younger lovers, all while harvesting pineal secretions.

A mysterious elderly woman who claims to have been brought to America as a slave 140 years ago and seeks eternal youth through a ritual involving orchid pollen and pineal secretions. She is the catalyst for the entire journey and its dangerous consequences.

Neil Foster's fiancée who becomes entangled in the love triangle and becomes a victim in the pursuit of pineal extracts.

A lawyer who falls for June (as Terry Hart) and becomes a potential target for the pineal extract. His affection drives part of the plot's romantic tension.

The jungle guide, a complicated figure who betrays trust by stealing the ring and pollen. He becomes a casualty of the ritual's consequences.

A male character associated with the expedition; the summary does not detail his role, but he is part of the story's circle during the Africa journey.