The Masque of Mandragora ( TV story ) The Masque of Mandragora was the first story of the 14th season of " Doctor Who " . It was notable for being the first historical or pseudo - historical story since " The Gunfighters " not to be principally set in Great Britain . It also introduced the first radical redesign of the TARDIS control room and offered the first explanation of how both the Doctor and his companion s were able to understand and communicate in languages other than English . Synopsis . An encounter with the living energy structure known as the Mandragora Helix leads the TARDIS to 15th century Italy . Between palace intrigue , the machinations of a sinister cult and a rogue fragment of Helix energy , the Fourth Doctor and Sarah have their hands full . There is not much time , for when Mandragora swallows the Moon , it will be time to strike . Plot . Part one . The Fourth Doctor shows Sarah Jane some of the other parts of the TARDIS interior . They come across the older console room which , unlike the primary room , is decorated with wood - panelling and has a more archaic feel . Activating the viewscreen , the Doctor sees a swirl of living energy in the time vortex — the Mandragora Helix — which starts to draw them in . The intelligence within the Helix starts to psychically attack them as the Doctor tries to pilot the TARDIS through it . The ship ends up inside the Helix itself . The Doctor and Sarah go outside but have to duck behind the TARDIS as a fragment of glowing Helix energy flies by . They escape in the TARDIS , not knowing that the fragment has entered with them . In 15th century San Martino , Italy , a peasant revolt is violently put down by Count Federico and his men , led by Captain Rossini . In a palace , Federico ' s brother , the Duke of San Martino , lies dying . He is attended by his son Giuliano and Giuliano ' s companion , Marco . The Duke ' s death had been foretold by Hieronymous , the court astrologer . Giuliano , a man of science , does not believe in such superstition . In fact , Hieronymous is working for Federico , and the horoscope ' s prediction of the Duke ' s death was helped along by poison . Hieronymous tells the Count that he feels his powers are growing , but all Federico wants is for the astrologer to foretell Giuliano ' s death next , and he will take care of the rest . The TARDIS materialises in a field near San Martino . The Doctor and Sarah go out to explore . Unseen , the energy fragment flies out of the TARDIS as well . Sarah wanders off and is kidnapped by a group of men in hooded robes . The Doctor tries to rescue her , but he is knocked unconscious . When he awakes , he witnesses the energy fragment fly towards and kill a peasant . Searching for Sarah , the Doctor is confronted by the Count ' s men and arrested . At the court , the Doctor tries to tell Federico that the energy fragment could spell the end of the world . The Count at first thinks the Doctor is a seer , like Hieronymous . When the astrologer quizzes the Doctor , it becomes clear that the Doctor does not believe in any of it . Federico orders the Doctor to be executed as a spy . Meanwhile , Sarah is brought before a priest . He tells her that she is the foretold sacrifice to Demnos , the Roman god of moonlight and solstice . She is dressed in a white robe and told that she will be sacrificed when the moon rises over the southern obelisk . Back at the palace courtyard , the Doctor is led to the executioner and forced to his knees for decapitation . Part two . Before the executioner ' s sword lands , the Doctor unfurls his scarf and hooks it around the executioner ' s ankle , throwing him off balance . The Doctor escapes out of the palace grounds and finds his way into some catacombs beneath the city . The guards , fearing the Brethren of Demnos who reside in those passages , stop their pursuit . Inside , Sarah is laid out on an altar . A purple - robed figure wearing a golden mask is about to stab her with a silver dagger when the Doctor snatches Sarah away . The fragment appears in the chamber , suffusing it with a red glow and providing a distraction for the two to escape . Giuliano examines the body of a guard that was killed earlier by the passage of the fragment , and while he does not know the cause of the guard ' s death , he dismisses ideas that it was some kind of fire demon . The Doctor and Sarah are found by some palace guards . In the temple , the Helix manifests itself as a pillar of red light and tells the purple - robed figure that he alone will be given undreamed - of powers to carry out its will on Earth and become the planet ' s supreme ruler . After the Helix vanishes , the figure removes the golden mask , revealing the face of Hieronymous . The guards bring the Doctor and Sarah , not to Federico , but to Giuliano , who shows him the dead guard ' s body and tells the Doctor of fears that if Federico rules San Martino , all knowledge and learning will be suppressed . Elsewhere , Federico discovers that Giuliano has invited several nobles to San Martino to celebrate his succession to the Dukedom . Angered , Federico demands Hieronymous make up a new horoscope and poison Giuliano before the next evening . The Doctor deduce s that the Helix chose San Martino because the Brethren provided a ready - made power base . The 15th century was the transition between the Dark Ages and the dawn of the Renaissance — the Helix could gain control of the Earth now through a new religion . The Doctor tells Giuliano the temple must be destroyed . They go to the temple , and the Doctor enters the catacombs alone , but as he enters the main chamber the Helix attacks him psychically . Rossini informs Federico of Giuliano ' s trip to the temple , and the Count decides to take his guards to the temple to kill his " pagan " nephew . The guards corner Giuliano with their swords . Sarah runs into the catacombs calling for the Doctor , but she is caught by the Brethren . Part three . The Helix attack stops , but the Doctor is prevented from venturing further into the temple . He leaves to find Giuliano fighting off the guards and joins in with a sword of his own . Giuliano is wounded , and suddenly , the Brethren emerge from the forest armed with staves and force the guards to retreat . The Doctor and Giuliano go into the catacombs . Sarah is brought back to the astrologer ' s chambers , where she is left gagged as the priest and Heironymous 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 brought back to the astrologer ' s chambers and is drugged and 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 begin to arrive , and Federico realises he does not have much time to eliminate Giuliano , but Rossini is unable to find Giuliano in San Martino . Hieronymous warns Federico that his life is in danger . Federico scoffs , believing Hieronymous to be a fraud , but he 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 make their way into the palace dungeons through a secret passage . The Doctor goes to confront Hieronymous , whom he has deduce d is the leader of the Brethren , in his rooms . Sarah secretly follows , trying to carry out her post - hypnotic orders . When the Doctor speaks to Hieronymous , Sarah sneaks up behind 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 and Sarah as well as 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 gathering on the streets and moving towards the temple . The Doctor tries to convince Federico that Hieronymous is the real threat . Federico wants to see for himself and takes the Doctor with him and some guards , leaving the others as hostages . In the temple , Hieronymous summons the Helix , which begins infusing him and his followers with power . Disguised in hoods , the Doctor , Federico and the guards enter and witness the ceremony . Federico steps forward , calls Hieronymous a traitor , and rips off the golden mask , only to reveal glowing energy in the place of a face . Hieronymous raises a finger , and electrical energy stabs out at the Count , reducing him to ashes . Part four . Hieronymous then fires at and kills the two guards as well , but he does not seem to have seen the Doctor . The Doctor joins the circle around the Helix as Hieronymous announces that Mandragora will swallow the Moon the next evening and then the Brethren will strike . The Doctor slips away unnoticed . Back in the palace dungeons , Rossini is about to kill the prisoners when the Doctor arrives and reveals that Federico is dead . With that , the guards change their allegiance to Giuliano and take Rossini into custody . The Doctor observes that the Brethren are still a danger . He tells Giuliano to fortify the palace in preparation for their attack . In the meantime , the Brethren are driving people out of the city , killing those who refuse with bolts of fire , isolating the palace . Giuliano wants to cancel the masque that will celebrate his accession , but Marco is confident they can defend the palace against the Brethren , and that to cancel the masque would be a sign of weakness . The Doctor does some astronomical observations and calculates there will be a lunar eclipse that evening — Mandragora swallowing the Moon — and when the Helix takes over , it will remove all sense of purpose from mankind . Right now , however , the Helix energy is spread thinly over all the Brethren , and it could be exhausted . He asks Giuliano for a breastplate and a length of wire . Wearing the breastplate under his coat , if he has guessed right about the nature of Helix energy , he could drain it off . Hieronymous knows of a secret way into the palace , and he intends to infiltrate his men under cover of the masque . The Doctor makes his way into the temple and grounds the altar with wire . Hieronymous addresses the Doctor as " Time Lord " , and says that Earth has to be possessed ; if mankind ' s ambition is not checked , it will eventually spread into the galaxy and the powers of Mandragora will not allow a rival within their domain . Hieronymous fires a bolt of energy into the Doctor ' s chest , knocking him back painfully , but the Doctor survives . More bolts fire into the Doctor , but he continues to egg Hieronymous on . At the masque , the Brethren make their appearance , with the masqueraders running about in panic , as they fire into the crowd , killing two . Hieronymous then appears and tells the Brethren to take the others down into the temple for the final sacrifice . The Moon goes into eclipse , and the Brethren place their hands on the altar as a ball of Helix energy descends . However , it consumes the Brethren instead , expanding and then fading away . " Hieronymous " removes his mask — revealing the Doctor , who was imitating the cult leader ' s voice . The Doctor explains it as a case of " energy squared " , putting the Mandragora Helix back where it came from . The Doctor and Sarah say their goodbyes to Giuliano . Just before they leave in the TARDIS , the Doctor tells Sarah that while Giuliano will not have any more trouble with Mandragora , humanity will . The constellation will be in position again in 500 years , at about the end of the 20th century . . . Story notes . Production errors . " to be added "