“The Adventure of the Greek Interpreter” is one of the 56 Sherlock Holmes short stories written by British author Sir Arthur Conan Doyle. Doctor Watson learns that 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.