The Adventure of the Greek Interpreter Sherlock Holmes, far from being a one-off in terms of his powers of observation and deductive reasoning, in fact has an elder brother whose skills, or so Holmes claims, outstrip even his own. As a consequence of this, Watson becomes acquainted with the Diogenes Club and his friend's brother, Mycroft. Mycroft, as Watson learns, does not have the energy of his younger brother and as a consequence is incapable of using his great skills for detective work: In spite of his inertia, the elder Holmes has often delivered the correct answer to a problem that Sherlock has brought to him.
The Adventure of Sherlock Holmes' Smarter Brother Sacker, shares a similar name with that originally applied to John Watson, Ormond Sacker. The film's title and premise are a joke referring to the character of Mycroft Holmes, Sherlock Holmes' "older" brother, who was by both of their estimates a good deal smarter than Sherlock. He was, however, too lazy to become a detective, and did indispensable work for the British government. Mycroft was described by Sherlock in conversation with Watson: Mycroft is mentioned briefly in the beginning of the film, which presupposes that Holmes was one of three brothers. Sigerson's name refers to an alias used by Sherlock