Ezra Jenning, Mr. Candy's assistant, bares out his duality physically. He is the son of an English father and a mother from one of England's colonies. He is dark skinned and Betteredge describes him as having "piebald hair," which is half black and half white. Franklin describes him as looking as young as forty or as old as Betteredge, who is in his mid-seventies. He has been rejected by thoses among whom he dwells due to his appearance, which has resulted in false rumors. Despite being a doctor's assistant, he has attacks which cause him to rely upon laudanum. Jennings decodes the message that Dr. Candy wants to give to Franklin and this message ultimately explains how the diamond left Rachel's possession. Despite his chaotic inwardness, Jennings is able to provide answers that otherwise would have been left unanswered.
Godfrey is another character of duality. He has a philanthropic side, as that is the side with which Miss Clack is most familiar. Betteredge describes this side of Godrey:
He is seemingly devoted to helping women through charity, but it becomes clear that he is just in it for the money. He sees marrying Rachel as an opportunity to clear his debts but a specific clause in Mrs. Verinder's will prevents his access to Rachel's money; therefore, the engagement is broken. Ultimately, he is discovered to have stolen the diamond but is killed by the Indians before he can pay his debts. The curse of the diamond has manifested itself by wreaking havoc everywhere it has gone until it is back in the possession of the Indians.
Collins shows human duality in other ways as well. He dresses the Indians up as jugglers visiting the neighborhood, though they are actually priests in search of the diamond. Franklin, in an opium-induced expedition, steals the diamond, which Godfrey takes uses as surety for a loan. Collins depicts man as a multi-sided personality.