Poole: He is Dr. Jekyll's man servant, chief butler, and all-around manager of the house; he has been in Dr. Jekyll's service for so long that he knows every footstep and motion associated with his employer; he is, therefore, able to report to Mr. Utterson that the man in seclusion is not Dr. Jekyll.
Bradshaw: Dr. Jekyll's footman and man-about-the-house, who goes around to the back entry of Jekyll's laboratory to guard the back door, while Poole and Utterson break in through the front door.
Mr. Guest: Mr. Utterson's secretary, who is "a great student and critic of handwriting." He finds something amazingly similar between Dr. Jekyll's and Mr. Hyde's handwriting.
Sir Danvers Carew: A distinguished M.P. (Member of Parliament), who does not appear in the work, but whose unprovoked and vicious murder by Edward Hyde causes a turning point in the novel.
Inspector Newcomen of Scotland Yard: The officer who accompanies Utterson on a search of Hyde's house in Soho after the murder of Sir Danvers Carew.