Mindwarp ( TV story ) Mindwarp was the unbroadcast title given to episodes five to eight of " The Trial of a Time Lord " , the season - long story that constituted Season 23 of " Doctor Who " . It was the second serial in the " Trial of a Time Lord " arc . It saw the final appearance of Peri Brown in the series from a present perspective and the guest appearance of Brian Blessed , who portrayed the role of King Yrcanos in his signature style of sonorous , magniloquent acting . Synopsis . As the trial of the Doctor continues , evidence is presented showing his most recent adventure - where he faces an old adversary , Sil . As a scientist conducts his unethical experiments to prolong the life of Sil ' s boss Kiv , the Doctor ' s memory of the events begins to return . . . and an unpleasant surprise awaits him . Plot . Part five . The Valeyard and the Doctor argue about the Doctor ' s involvement in past events . The Inquisitor warns them to pay due respect to the judicial process . The Valeyard presents his second block of evidence - the Doctor ' s arrival on the planet Thoros Beta . The TARDIS arrives on the planet , where the Doctor shows Peri a weapon given to him by the " Warlord of Thordon " , made on Thoros Beta . He says he has come to find out how the warlords obtained the technology . They enter a cave . Peri is grabbed by a monstrous creature . In the struggle the Doctor shoots it . The Valeyard accuses the Doctor of deliberately shooting the monster , but he insists the weapon went off accidentally . A figure arrives and accuses the Doctor and Peri of murdering the Raak , despite their protestations that it attacked them first . The figure asks if they are part of Crozier ' s group . The Doctor says he is . They flee before they can be identified as imposters , but are quickly faced by another monster . It reacts kindly when the Doctor is nice to it . They flee further . As they hide , they see three reptilian figures being carried by guards . The third is their old enemy Sil . The Doctor realises Sil is probably behind the arms sales , and informs Peri that Thoros Beta is the home world of Sil ' s race , the Mentor s . In Crozier ' s laboratory , King Yrcanos is being experimented on . The Doctor and Peri sneak inside . As the Doctor sabotages some of Kiv ' s equipment , Sil arrives in the laboratory . The Doctor is strapped to a table and Crozier applies a metal helmet to his head . Crozier states that the equipment will extract the truth from a suspect and could prove fatal . He starts to probe the Doctor ' s mind , and the Doctor screams in agony . . . Part six . King Yrcanos awakes and destroys the equipment . Overpowering the guards , he departs the laboratory , followed by a stunned Doctor and Peri . Yrcanos outlines his plans to attack the Mentors . The Doctor says he would enjoy that , and then collapses . The Doctor tells the Inquisitor that he cannot remember these events . The Valeyard tells him he is in for a surprise if this is true . Yrcanos , the Doctor and Peri go to where new slaves are brought into the base . Yrcanos plans to attack the guards and steal their weapons , but as he sneaks into the room , the Doctor calls out to the guards , giving him away . Yrcanos , unable to fight the guards , flees . Peri points a weapon at Sil , and asks the Doctor for help , but he ignores her . Peri drops the weapon and flees after Yrcanos . Sil asks the Doctor why he helped the Mentors , and he replies that the odds were on their side . The Doctor insists that the footage is not of him , but the Valeyard tells him that the Matrix cannot lie . Peri comes across Matrona , who allows her to join the Mentors ' servants rather than turn her over to the guards . Covered with a veil , she enters the Commerce Room with Kiv ' s medication . The Doctor calls to her to get him a drink , so she disguises her voice to avoid being recognised . When she brings him a new drink , the Doctor uncovers her and denounces her as an enemy to the Mentors . The Doctor tells the courtroom that what they are seeing is all part of his ploy . He says he planned to gain the Mentors ' trust so that he would be allowed to interrogate her alone , giving them a chance to escape . Peri is lashed to rocks on the shoreline and the Doctor stands over her , accusing her of being a spy . She asks why he is behaving the way he is , and the Doctor tells her that Crozier is planning to put Kiv ' s brain into his body unless he can help them . Crozier stops the interrogation , saying that they have more effective methods of extracting the truth from Peri . As they re - enter the complex , Yrcanos attacks the guard and threatens to kill the Doctor . . . Part seven . However , Peri smashes the gun from Yrcanos ' s hands , allowing the Doctor to flee . In Crozier ' s laboratory , the scientist prepares to transplant Kiv ' s brain into a recently deceased Mentor corpse with the help of the Doctor . The operation proves successful . Meanwhile , Yrcanos , Peri and Dorf team up with members of the Alphan resistance . Agreeing to allow Yrcanos to lead them in an attack on the Mentors , they go to the resistance arms dump , but they are ambushed by Mentor guards and shot down . However , it is revealed they have merely been stunned , and they are taken to cells . In Crozier ' s laboratory , Lord Kiv is rambling due to the body of the fisherman influencing his brain . Crozier makes plans to transfer the brain into another more suitable body , and suggests using Peri . The Doctor says he would prefer that she is not experimented on , but while he is trying to find another candidate , Peri is brought to the laboratory and strapped to the operating table . Crozier begins to prepare her for the surgery . Watching these events on the Matrix screen in the Time Lord courtroom , the Doctor protests that he was not responsible . The Valeyard , however , replies , " In your mind , perhaps not . But in reality it is somewhat different , Doctor . " The Doctor looks perturbed . . . Part eight . The Doctor goes to Yrcanos ' s cell and tricks the guard , allowing Yrcanos and Dorf to escape . Together they free the remaining resistance members . They head towards the control room , from where all the slaves are mentally controlled . They succeed in freeing the slaves from mental control , but Dorf is killed by a passing guard . Lord Kiv is taken to the laboratory to prepare for the operation . Peri is strapped down and gagged , and Kiv gives the order to shave her head . As the Doctor heads towards the lab , he is summoned by the Time Lords and promptly vanishes . The Inquisitor tells the Doctor this was the result of an order from the High Council , because the result of Crozier ' s experiment would affect all life in the Universe . As Yrcanos prepares his attack on the laboratory , the Time Lords capture him in a time bubble so that his attack is perfectly timed to destroy Crozier ' s work . When Kiv awakes in Peri ' s bald body , the time bubble dissipates and Yrcanos bursts into the laboratory . He is consumed with fury and begins firing his gun wildly , killing Peri and the others in the process . The Doctor is shocked by what he has seen . The Inquisitor and the Valeyard tell him that it was necessary to end Peri ' s life to prevent the disastrous consequences of Crozier ' s experiment . The Doctor insists that he was fetched out of time for some other reason , and he is going to find out why . . . Home video and audio releases . DVD releases . DVD Contents