A sharp-witted man with a reputation for his excellent powers of deduction. A highly rational person who does not approve of emotions.
The Sign of the Four (Grades 9–1)
The narrator of the story, he adds human feelings to the events. He falls in love with Mary and asks her to marry him.
Well dressed but of limited financial means, she has a refined and sensitive nature. She is realistic about her possible inheritance.
An anxious and nervous character, as shown by his odd behaviour. He wishes to do the right thing and tries to help Mary.
A poorly-educated convict, who recognises at the end of the novella that his greed has always brought him bad luck.