Watson returns to the flat where he meets Holmes, Jones, and Small. Small admits that, during the boat chase, he scattered all of the jewels in the river as he believes only those in the sign of the four are entitled to it. Holmes allows Small to tell his side of the story in order to learn just why he should be entitled to the treasure. 

Small starts by saying he began life rather happily, joining the army because a relationship he had with a girl became soupy and, after being sent to India, a crocodile bit his leg off. After healing, he was positioned as an overseer of a plantation but he witnessed the Indian Mutiny, which took his superior’s life. He managed to escape on a horse and set up in Agra. 

Whilst there, he joined a volunteer corps and found two men under his command: Abdullah Khan and Mahomet Singh. It turns out that one of these men threatened Small with a knife, forcing him to be with them or against them in one of their plans. Small agrees so long as the plan doesn’t involve harming anyone in Agra. 

The men explain that the Agra treasure is the result of a wealthy Rajah vowing to split his treasure and give one half to whichever side of the new mutiny wins. Abdullah reveals that his foster brother, Dost Akbar, the fourth man in the sign of the four, is travelling with the Rajah’s merchant and the treasure, affording them the perfect opportunity to split the treasure between them. 

Come the night of the plan, all is proven to be successful. The murder of the merchant gives them all the luxury of looking at the treasure and noting its bountiful wonder. The four then keep to their promise and conceal it all within the walls of Agra in order to wait for the end of the horrors of the new war. 

However, even though the conflict cooled, all four men were arrested when it was revealed that another man was following the merchant to make sure he fared well enough. Their crimes were discovered and all were forced into penal servitude. 

Small was sent to the Andaman Islands where he appeared to get along well, learning about medicine and so forth, and meeting Major Sholto and Captain Morstan. Sholto loses a good amount of money playing cards one night with the guards and Small tells him and Morstan of the treasure and says he’ll help them retrieve it if he is given his freedom. 

They agree and Small wishes to make sure the others bound in the sign of the four agree. Sholto feels it is useless and unnecessary to get them involved. Sholto eventually betrayed all when he deliberately failed to report about the treasure’s location, taking the wealth back to England with him and never returning to the Andaman Islands. Small then became motivated to find Sholto. 

It was around this time that Small met Tonga, who was sick, but became loyal to Small when he brought him back to health with his new knowledge of medicine. Tonga aided Small in his escape with a boat and the pair set sail, on many adventures, before coming to England roughly four years ago. 

When he found Sholto to be near death, he used it as an opportunity to search for where the treasure was now hidden and his message detailing the sign of the four was representative of the men he had wronged. 

During the wait for the treasure’s discovery, Small exhibited Tonga as the ‘black cannibal’. Finally, from an insider, he received information that the valuables had been unearthed, also telling him of the trapdoor in the house’s roof. Tonga scaled the building with Small attached to him via a rope but Tonga killed Bartholomew, which angered Small. The two now fled, after gathering the jewels, to hire the Aurora. 

Small’s story is concluded and Jones offers his praise to Holmes for the assistance. Holmes, whilst elated with the solving of the case, is then made concerned when Watson informs him of Mary’s agreement to marriage, as it may spell his last case with him. Watson then states that he feels it is a tad unfair. 

Jones gets his culprit and Watson gets Mary, but Holmes receives nothing. Sherlock then reminds Watson that the case’s completion is all the reward he needs and, besides, he still has his cocaine.