Holmes secretly meets with Watson and Elizabeth and begins his investigation into the murders. During their investigation, the trio uncover the existence of Rame Tep, an ancient Egyptian cult of Osiris worshippers who used blowpipes and hallucinogenic darts to kill their victims. . Holmes, Watson, and Elizabeth track the cult to a London warehouse, where the Rame Tep are performing human sacrifices in a secret underground wooden pyramid. The trio interrupt the sacrifice of a young girl and are pursued by the Rame Tep who shoot them with thorns. They experience terrible hallucinations but survive. Holmes, Watson and Elizabeth are later reprimanded by Lestrade, who still dismisses Holmes' deductions. Holmes leaves him several poison thorns for analysis, and Lestrade pricks his finger on them as he tries to brush them off his desk.