catacombs alone. Giuliano tells Sarah that he and a few others believe that the earth is a sphere (although that was common knowledge of the day). As the Doctor enters the main chamber the Helix attacks him psychically. Rossini informs Federico of Giuliano's trip to the temple, and the Count decides to kill his "pagan" nephew. The guards corner Giuliano and attack. Sarah runs into the catacombs calling for the Doctor, but is caught by the Brethren. The Helix attack stops, but the Doctor is prevented from venturing further into the temple. He leaves to find Giuliano fighting the guards and joins in. Giuliano is wounded and the Brethren emerge from the forest and force the guards to retreat. The Doctor and Giuliano enter the catacombs. Sarah is brought back to the astrologer's chambers where she is left gagged as the Priest and Hieronymous talk. The priest is eager to sacrifice Sarah, but Hieronymous decides to use her as bait for the Doctor. Hieronymous allowed the Brethren to save Giuliano because the young prince may still have value. Sarah is hypnotised to believe the Doctor is an evil sorcerer. Hieronymous gives her a poisoned needle to kill the Doctor. At the palace, the invited nobles arrive and Federico realizes he does not have much time to eliminate Giuliano, but Rossini is unable to find Giuliano. Hieronymous warns Federico that his life is in danger. Federico scoffs, believing Hieronymous a fraud, but is suspicious enough to tell Rossini to banish Hieronymous from the city. In the catacombs, Giuliano and the Doctor find Sarah, who cannot remember anything after her capture by the cult. They reach the palace dungeons through a secret passage. The Doctor confronts Hieronymous, whom he has deduced is the leader of the Brethren. Sarah secretly follows. When the Doctor speaks to Hieronymous, Sarah sneaks up behind him with the needle, but the Doctor snaps her out of the trance, just as the guards come for Hieronymous. The astrologer escapes, but the guards capture the Doctor, Sarah, and Giuliano. In the dungeons, Federico accuses the prisoners of being followers of Demnos. Rossini rushes in, informing the Count that members of the Brethren are moving towards the temple. The Doctor tries to convince Federico that Hieronymous is the real threat. Federico takes the Doctor with him and some guards, leaving the others as hostages. In the temple, Hieronymous summons the