Evil and justice in The Sign of the Four

The themes of evil and justice are closely related in this novel. Evil is present in the form of the murders and crimes that are committed. It is also embodied by the character of Tonga who is depicted as inherently savage and malicious.

Justice is sought on behalf of Miss Mary Morstan. Thaddeus Sholto feels that Miss Morstan has been treated unjustly by his father, Major John Sholto, who kept the Agra treasure, and kept the facts of her father’s death a secret.

Jonathan Small is upset by the injustice that he will never enjoy the treasure that he believes is rightly his, despite the fact that he acquired it by murdering a man. Holmes is fair and insists that Small will not be accused of murdering Bartholomew Sholto.

How is the theme of evil and justice shown in the novel?

In The Sign of the Four, Conan Doyle shows the theme of evil and justice through:

  • Miss Mary Morstan and her missing father
  • the character of Tonga
  • the sense of injustice that Jonathan Small feels in losing the treasure
How does Conan Doyle show this?EvidenceAnalysis
Miss Mary MorstanMiss Mary Morstan shows Holmes a letter she has received that says she deserves justice.You are a wronged woman, and shall have justice.The mystery is established, and the reader is intrigued to discover what sort of justice she is owed. The safety of Miss Morstan's father is also in question.
TongaThe character of Tonga is presented as the embodiment of evil in this novel.Never have I seen features so deeply marked with all bestiality and cruelty. When Watson sees the islander on the boat, he is struck with the savage appearance of the man.
Major John SholtoOn his deathbed, Sholto confessed to his greed.The cursed greed which has been my besetting sin through life has withheld from her the treasure.Sholto hides the death of Miss Morstan's father out of fear and hides her entitlement to the treasure out of greed. This greed can be seen as the source of evil.
Holmes suggests he can help SmallEven though Small has committed a crime, he is not guilty of the murder of Bartholomew Sholto."I think I can prove that the poison acts so quickly that the man was dead before you ever reached the rooms."Holmes' sense of justice means that even though he has pursued Jonathan Small, he does not want him to be punished for a crime he did not commit.

Analysing the evidence


How does Conan Doyle use the theme of evil and justice in this novel?

  • To show how evil and injustice stem from greed.
  • To show that justice prevails, and that acting unjustly brings unhappiness.
  • To explore human nature.