The Stones of Blood ( TV story ) The Stones of Blood " was the third story of season 16 of " Doctor Who " . It was the show ' s one hundredth television story . Part four was first broadcast the week of the show ' s fifteenth anniversary . Synopsis . Searching for the third segment to the Key to Time brings the Doctor and Romana I to present - day Earth , where the travellers have to contend with stone circle s , Druid ic rituals and a not - so - mythical goddess known as the Cailleach . Plot . Part 1 . The Fourth Doctor and Romana I are about to embark in search of the third segment of the Key to Time . The Doctor is excited to find that it is located on Earth , which Romana describes as his favourite planet . Romana has dressed herself in a fashionable outfit , including a pair of four - inch heels that the dismayed Doctor believes will be unsuitable for walking . They prepare to embark when a voice tells them to " beware the Black Guardian . " At this , the Doctor reveals Romana was not sent on this quest by the President of the Time Lords , but rather by the all - powerful White Guardian , who wishes them to gather the Key to maintain galactic stability . They venture outside to find themselves near the Nine Travellers , a group of cromlech or standing stones in Boscombe Moor , Cornwall . On the way , they see heavy indentations in the ground , which intrigue the Doctor . Also interested in the location is aged archaeologist Professor Amelia Rumford , who is surveying the stones with her friend , Vivien Fay . They find dried blood on the ground at the stones and are alerted to the activities of a local druidic sect . The Doctor goes to meet its implied leader , Leonard de Vries . Romana , having difficulty walking in her heels , stays behind with Amelia and Vivien . De Vries lives in a large property nearby , Boscombe Hall , built on the site of the Convent of the Little Sisters of Saint Gudula . Inside , de Vries and his maid , Martha , are incanting to the Cailleach , the Druid ic goddess of war and magic . The Doctor interrupts and is entertained briefly by de Vries until his host sees the opportunity to knock him out . De Vries and his mistress , dressed in a hideous bird costume , aim to sacrifice him to the Cailleach . Meanwhile , Amelia and Vivien prepare to go back to Vivien ' s cottage . They invite Romana to join them for a cup of tea , but she opts to stay at the circle to wait for the Doctor . After the others have left , Romana hears the Doctor ' s voice calling out to her . She calls out for the Doctor . When he does not answer , Romana decides she should investigate — in her bare feet . Her high heels have caused her so much ilk she pitches them . Romana approaches a cliff edge , still hearing the Doctor call out . Something disturbs her , and she yells for it to keep back . She steps backward and falls over the edge . Part 2 . Romana has grabbed onto the rock face and is clinging to the cliff just below the edge . Meanwhile , de Vries and Martha argue about the validity of sacrificing the Doctor , who is now awake and tied to one of the stones in the circle . The sacrifice is interrupted by the arrival of Professor Rumford , who frees the Doctor as the others flee . Neither the Doctor nor Amelia knows where Romana is , however . After discovering her abandoned shoes , the Doctor summons K9 to help find her . They are successful . Romana is relieved to see K9 but is surprisingly mistrustful when she sees the Doctor . After they pull her up from the cliff , K9 calms her by assuring Romana it is indeed the Doctor . They conclude that it must have been a doppelganger of him who pushed her off the cliff . They assume that whoever it is must be in possession of the third segment of the Key to Time and has found a way to utilise its shape - changing abilities . They decide de Vries can answer some questions and set off for Boscombe Hall — after Romana is allowed to return to the TARDIS so she can change clothes and switch into a pair of sturdy boots . When he gets there , he finds the owner and Martha have been crushed to death . The Hall is under attack by a pair of mobile giant stones like those from the moor . The Doctor and K9 repel the attack , though the robot dog is badly damaged and needs repair in the TARDIS . More curious facts come to light : the Doctor works out that the stones need blood to survive . Romana has pieced together that the owners of the Hall and the preceding convent were all women . It soon becomes clear they all had the same face too — that of Vivien Fay . Meanwhile , the woman in the bird costume has brought more stones ( or Ogri , as she calls them ) to life using poured blood . Romana ventures back to the stone circle and there finds Miss Fay in the costume . When challenged , she fires a weapon at Romana , causing her to dematerialise . Part 3 . Meanwhile , after dispensing with one of the stones pursuing them , the Doctor and Professor Rumford reach the stone circle . Miss Fay tells them Romana will be safe if the Doctor stops interfering . She disappears . The Doctor now identifies the stones as Ogri , a life form from Ogros in the Tau Ceti system . Two of them are still missing and moving around the countryside . Two innocent campers help quench their taste for blood . The Doctor calculates Romana and her captor must be in hyperspace . He builds a projecting device which he uses to transmit himself there . He arrives on a hyperspace craft which seems to be a prison vessel , and he frees Romana . He soon breaks a lock on a sealed door , releasing two floating globes . They are Megara , justice machines , dispensing the law as judge , jury and executioner . They contend that as the Doctor broke the seals , he has transgressed the law and should be eliminated . K9 and Amelia have meanwhile been tasked with protecting the projector used by the Doctor to cross the dimensions , but they find themselves under attack from two Ogri . Vivien returns to Earth and destroys the device but spares her friend . She takes the Ogri back to the hyperspace vessel with her and there tells the Doctor and Romana she has destroyed their linking device between the dimensions , leaving them trapped in hyperspace forever . Part 4 . The Megara destroy one of the Ogri that threatens them . The Doctor has been tried in his absence by the Megara , an abrupt and unfair process dependent on the word but not the spirit of the law . He successfully petitions to conduct his own defence in an appeal . He puts Romana in the witness chair to establish that he broke the seal because he feared for the safety of the Megara . This also sets a precedent for the use of the truth assessor . He tries to draw Vivien Fay into the trial and get the Megara to subject her to the truth assessor , which will reveal her true identity to the court as the person whom they were originally set to put on trial 4000 year ago . When he calls " Vivien " to the stand , he argues she should be attached to the assessor like Romana . The Megara , however , deny his appeal on the grounds that she was not a direct witness to the crime for which he stands accused . Nevertheless , the Doctor comes closer to the truth about " Vivien " . He argues successfully for putting one of the two Megara on the stand , who tells the court the nature of the journey that has kept them in hyperspace for four thousand years . They are on a mission to find and try Cessair of Diplos , a criminal wanted for murder and the removal and misuse of the Great Seal of Diplos . The Megara states the seal has significant powers : transmutation , transformation and the ability to establish " hyperspatial and temporal coordinates " . Amelia and K9 have repaired the projector and use it to beam Romana back from the hyperspace vessel — and the one surviving Ogri , which chases them . They find incriminating data at Miss Fay ' s cottage — cookery books in which a number of recipes containing citrus fruit juices have been crossed out ; Amelia says that Miss Fay was allergic to citric acid . Romana and the Ogri return to the spacecraft to await the verdict . At the close of his trial , the Doctor is convicted and the Megara fire executing beams at him . He drags Vivien into the beams ' focus . The energy is divided between them , so both survive . This forces the Megara to examine her to see if she is badly hurt . The Doctor suggests they must examine her mind to check for damage . They find she is indeed Cessair of Diplos . She is charged with her crimes when she wakes , and the last Ogri is confined in a cell aboard the ship to be returned to its own planet . Cessair is sentenced to confinement for fifteen hundred years and perpetual imprisonment , the sentences to run consecutively . Before she is turned into a stone on Boscombe Moor , the Doctor grabs her necklace — the Great Seal of Diplos , which is in fact the third segment of the Key to Time . As the Megara bring up the matter of the Doctor ' s delayed execution , they suddenly return to their ship as it is about to leave . The Doctor set the controls to go , prior to his leaving the ship . The Doctor , K9 and Romana return to the TARDIS , thanking Amelia for her assistance . He uses the tracer to turn the third segment of the Key to Time to its proper form . As he struggles with putting it together with the other two , he looks over to Romana , reminded of her boasting of being good with such puzzles . Home video and audio releases . DVD releases . Contents ( 2007 / 2009 version ) : Notes :