Professor Smith's journal contains a retelling of strange events that occurred 30 years ago, in the spring of 1893.
Colleagues and friends of a young Julius Smith are hastily summoned to an address in Islington. The professor meets them there, in a rented room where a dying man lies on a bed with a doctor at his side. The exhaustive and uncommunicative patient is naked except for a red fez in his head that cannot be removed, and signs shown he was tied to this bed for days against his will. The poor man does not last long - he exhales his final agonizing breath, the fez falls to the ground, and the lights go out. Seconds later, the doctor shrieks in pain as the corpse's tongue extends to an impossible length and grabs him by the face. The investigators fight and defeat the reanimated corpse, and then collect the mysterious Fez for further research.
Despite never having met the dead man before, prof. Smith has a good idea as to his identity: recently, Smith has been in touch with Professor Demir of Instambul, a fellow occult researcher, who had sent one of his students to London to follow cult activity. He shares the telegraphs:
Pook, the dead man, was brought to the rented room three days before by men of apparent Turkish descent, all wearing fezzes. He was heard screaming in ever more rising agony, that his captors attributed to a detox procedure.
The investigators break into Pook's house, where they locate his journal holding his final recordings.
Research on the Blood Red Fez produces a few important pieces of information.
Examining the home of the fez collector whom Menkaph's men stalked and killed, the investigators discover that the collector had recently come into the possession of the rare tome The Whispering Fez. The book was delivered to the collector's home but is now missing - most likely, this tome was at the center of the crime.
The investigators decide to heed professor Demir's advice and bring the Fez to him in Istambul to have it destroyed. The fastest way to travel across the continent is the Orient Express, needing less than four days to get to their destination. The investigators hastily prepare for the trip and board the train the next day.