Describe the visit to the Diogenes Club in "The Greek Interpreter."

Sherlock tells Watson that the Diogenes Club "contains the most unsociable and unclubable men in town," where, but for one room, "no talking is, under any circumstances, allowed." Sherlock says that the Diogenes Club has a "very soothing atmosphere."
When Sherlock takes Watson to the Diogenes Club, Watson first describes a "large and luxurious room" full of men reading newspapers. Sherlock takes Watson to a small room, where he introduces him to his brother, Mycroft. We can assume that this room is "the Stranger's Room," the one room in the club where talking is permitted.
In "the Stranger's Room," Holmes, Watson and Mycroft are joined by Mr. Melas, an interpreter. Mr. Melas tells the others, but specifically Holmes, about something that happened to him earlier in the week. He says that he was taken to a house in a secret location. There he was asked to interpret the words of a Greek man, a hostage. The Greek man looked to be in distress—he was "deadly pale and terribly emaciated," and his face was "grotesquely criss-crossed with sticking-plaster." Mr. Melas tells all of this to Holmes in the hope that Holmes will be able to solve the mystery of the identity of the Greek hostage.