The towering and violent property owner of Jamaica Inn, he is involved in criminal activities like smuggling and is married to Mary’s Aunt Patience. His formidable presence is a persistent threat to Mary.

The youngest of the Merlyn brothers, he is both a criminal and Mary’s main romantic interest. His roguish honesty and adventurous nature stand in contrast to his brother Joss's brutality.

Mary’s maternal aunt, who once was lively but has now become timid and submissive due to years of abuse from her husband, Joss. Her loyalty to Joss highlights the cycle of domestic abuse.

The Vicar of Altarnun, near Jamaica Inn, initially appears as an ally to Mary but has a mysterious and enigmatic nature. His pale complexion and unusual demeanor make him a notable, if unsettling, presence.

The local magistrate and former owner of Jamaica Inn, serving as the narrative's representation of law enforcement. His ineffectiveness underscores the challenges Mary faces in seeking justice against Joss.