It is Ludwig's turn to be indisposed this time, laid up with a severe cold. Brought on, no doubt, by his recent shock and by the cold weather.

The next week passes quietly, with Aubrey and Georgina spending time in study of Talbot Estus' heavily-annotated copy of "The King In Yellow". The book is more allusive and less direct that "The Wanderer By The Lake", but all the more disturbing in what it implies. Georgina is much troubled by voices during the week, although no one else seems to hear what she does.

On the Tuesday they speak with Graham Roby, older brother to Alexander. Graham is a senior investment banker with Coutts. He is married with two children, lives in a large house in Belgravia, and is possessed of a well-groomed beard and an impressive poker-face. He does not seem particularly pleased to see the investigators: he is keen to know if they intend to recommend Alexander's release, and is disappointed when they say that they do. He describes his brother as a weak man whose interest in the occult and foolish attachment to an unsuitable girl led him into bad company, but he does not believe him capable of murder. Alexander was discovered in his room with the window broken - perhaps he blames himself for failing to stop the mysterious attackers? In any case, he believes that Alexander was broken by the experience; no one who knew the way he was before could think that a cure would even be possible.

The investigators pursue several lines of questioning. Graham claims not to remember much of Alexander's occult interests, which he considers foolish, but when pressed he is able to recall a few details. They included alchemy, psychoanalysis (in which Graham does not believe), and theosophy. He met his unsuitable fiancée at some kind of occult meeting, and Graham believes that she introduced him to unsuitable companions. It was his concern that these companions had designs on Alexander's share of the family money that led him to have his brother followed by a private detective. He considers this a reasonable precaution, and is concerned that they might seek Alexander out again if he is released. When questioned about the exact circumstances of the murders, his poker-face slips slightly. He offers no new information but is clearly nervous. He also seems concerned that Alexander should not be declared competent to manage his own finances. Perhaps he has something to gain from the current situation? The investigators make a note to ask the police about Herbert Roby's will.

A chat with the Roby family cook, now working for Graham, reveals a further significant detail. The sound of a whistle was heard from upstairs just before the attacks. The detective in charge found a whistle in Alexander's room and blew it for the servants, who confirmed that its sound was what they had heard. She describes the whistle as black and oddly-shaped. No record of this appears in the police file for the Roby case, although the full transcripts have not yet been made available.

On Friday, they visit Vincent Tuck and hear the results of his investigations. Bacon lives alone in a house near King's Cross, and apparently never leaves it. He keeps odd hours - there is always at least one lighted window at night. Apart from delivery-boys, his only visitor this week was an antique dealer named Jones. Quarrie worked for the Royal Society as a specialist in Anglo-Saxon folklore, but left in early 1926. A former colleague describes him as a solitary man with no friends or close attachments; he believes that Quarrie left for the Continent. Delia, Alexander's sometime fiancée, is now married an lives in Enfield. No trace of Edwards can be found. Before coming to London, Quarrie was at Oxford University and published a book: "British Gods: Religion and Myth in the Western Kingdoms of Anglo-Saxon Britain" (OUP, 1924). For want of a better idea, the investigators dispatch Tuck to Oxford to see what he can find.

That afternoon, the investigators call on Mr Jones, the antique dealer. He knows nothing of Carcosa or the Yellow sign. His dealings with Bacon were purely business, and not as much now as in previous years. Bacon has been growing increasingly bad-tempered and reclusive. A visit to Bacon's house confirms this. Even with an introduction from Jones, Bacon will not speak with the investigators. He smiles at a mention of Carcosa, but will tell them nothing and eventually calls the police to chase then away.

Lacking further leads, the investigators decide to contact Delia Morrison. They visit Enfield on Monday , hoping to avoid her husband - a wise choice, judging from her haggard manner and bruised face. Delia met Alexander in May 1925 at a Theosophical meeting and attended many lectures and study-groups with him. She describes his interests as Theosophy, psychology, and theories of thought-transference and mental influence. His interest, he said, was sparked by the strange dreams that he had experienced since childhood; it was these dreams, too, that inspired his book. It was in connection with the book that he met Edwards, Quarrie, and Bacon. She felt they were somewhat shady and refused to meet them despite Alexander's urging. Alexander gradually became consumed by his obsessions, and by the end of the year she was compelled to break off the engagement. She saw him only once after that, in late December 1925. He spoke of a meeting to held at the the turn of the year at Clare Melford in Suffolk. Nine standing stones had been prepared; she should see how beautiful they were, under the winter stars. She refused to have anything to do with it and never saw him again, although she read about the murders and his commitment to an asylum. She wishes him well, but wants no more to do with him; if she remembers anything that might help the investigators at his hearing she will forward it to them.

On returning to London, the investigators meet Ludwig, now mostly recovered and in a state of some excitement. That morning, he received a mysterious letter....