Time and the Rani ( TV story ) Time and the Rani was the first story in season twenty - four of " Doctor Who " . It marked the debut of Sylvester McCoy as the Seventh Doctor . Kate O ' Mara made her second and final televised appearance ( not including the charity special " Dimensions in Time " ) . It was also the series ' s first exploits with computer - generated imagery , a relatively limited technology at the time . An all - computer animated opening titles sequence was introduced with this story , along with a new arrangement of the theme tune by Keff McCulloch , an appropriately electronic rendition composed entirely on a Prophet 5 Synthesiser . The logo of the series was also changed into a three - dimensionally animated part of the title sequence , and became the series logo that would stay in use until the early 1990s . Following the circumstances of Colin Baker ' s exit from the role , the Sixth Doctor was made to immediately regenerate into the Seventh Doctor at the start of this story , so while " The Ultimate Foe " was the last story to feature Colin Baker as the Sixth Doctor , " Time and the Rani " was the final appearance of the Sixth Doctor properly , though not played by Colin Baker himself . Baker " was " offered the chance to reprise the role of the Sixth Doctor in a proposed regeneration story , but he declined ; he instead asked to be given a full season for his departure , but the denial of this request prompted him to turn down the reprisal . As a result , a pre - credits sequence was added into " Time and the Rani " featuring the Doctor ' s regeneration , with McCoy portraying both the Sixth and Seventh Doctors ( to hide this , his face remained hidden until the end of the regeneration sequence ) . The cause of the Sixth Doctor ' s regeneration is not explicitly shown on - screen , although he is seen being thrown across the console room as the TARDIS is pulled down during flight by the Rani . " Spiral Scratch " and " The Brink of Death " both provide narratives for the Sixth Doctor ' s regeneration , with both retroactively leading into the events of this serial . Synopsis . The Rani has returned after her last encounter with the Doctor , with yet another malicious scientific scheme . Taking advantage of the post - regenerative trauma the recently regenerated and unstable Doctor is going through , the Rani hopes to achieve control of an approaching asteroid composed entirely of strange matter . Can the Doctor figure out he is being used for the Rani ' s evil experiment , and what is behind the door the Rani won ' t allow the Doctor past ? Plot . Part one . While the TARDIS is flying through space , it is assaulted by multiple energy beams from the planet Lakertya , before being captured in a tractor beam . A native watches the TARDIS land nearby . The Rani and her servant break into the TARDIS , where they find both the Doctor and Mel are unconscious from the forced landing . On the Rani ' s orders , the beast ignores Mel and turns the face - down Doctor around , revealing that he ' s covered in a swirling spiral of blurry colours . In the following moment , the features of this Doctor fade along with the light , leaving a freshly regenerated new incarnation in place of the old Doctor . In the Rani ' s lab , it is revealed that she has used the Tetrap s to force the Lakertyans into helping kidnap an array of genius scientists throughout time , including Albert Einstein , Louis Pasteur , and Hypatia . She now also requires the Doctor . Angered by the incompetence of her workers , the Rani scares away a female Lakertyan . The Doctor recovers from the crash and seemingly is continuing a conversation his previous incarnation was having with Mel . He then notices that he is no longer in the TARDIS , has just regenerated and recognises the Rani . Angered by her presence , he wonders what kind of monstrous experiment she is up to now . He takes up his umbrella to strike her . The Rani knocks him out with a laser gun and injects him with an amnesia - inducing drug . She disguises herself as Mel . Once the Doctor recovers , she attempts to convince him to repair some broken machinery in " his " lab . Beyond the lab is a closed - off chamber . Mel has meanwhile been left behind in the TARDIS . She encounters , and eventually wins the trust of , the young hot - headed Lakertyan Ikona , who is eager to dispatch the evil Rani and liberate his people . In the meantime , the Doctor has returned to the TARDIS to change his clothes as he finds the clownish outfit of the Sixth not a fitting match for his new persona . After failing with several outfits ( including a Napoleon outfit , a British guard outfit , a schoolteacher outfit , a cricket outfit similar to that of the Fifth Doctor , one of the Third Doctor ' s outfits , and the Fourth Doctor ' s burgundy outfit ) , the Doctor walks out from behind a clothes rack wearing the Second Doctor ' s fur coat , but opens it to reveal his new outfit , which the Rani finds befitting of a Time Lord . As Mel and Ikona flee from a Tetrap , Mel trips one of the Rani ' s traps . She is encased in a large bubble and thrown over a cliff . Part two . Mel ' s bubble lands safely in a lake , and Ikona is able to free her . They flee from Urak . The Doctor and the Rani return to the lab , where the Doctor finds the problem and instructs " Mel " to return to the TARDIS and retrieve a tool . While doing so , the Rani orders her minion to kill Mel . Once the Rani returns and gives the Doctor the device he needs , he sees one of the mineral plates inside the device is broken . The Rani tells the Doctor that she can get a replacement from the locals , contradicting her earlier statement that they were not advanced enough for the Doctor ' s technological knowledge . The Doctor catches this as she leaves , realising that he has been duped . While the Rani leaves , Mel enters the lab and the Doctor mistakes her for the Rani . Mel , not recognising the Doctor due to his new face and clothes , wonders what he has done with the Doctor . After Mel mentions carrot juice and the Doctor responds with his great hatred of the beverage , they soften towards each other . He finds that she doesn ' t have a double pulse as a Time Lord would , and they accept that they are who they say they are . Mel says she knows about regeneration , but is still surprised to find his appearance and height completely different . They decide to find out what the Rani has been planning . In an inner chamber , Beyus and Faroon show them an enormous brain that channels the kidnapped scientists ' mental ability into a single gestalt mind . An asteroid composed entirely of strange matter , a very rare and super heavy material , is passing nearby . The Rani has constructed a fixed - trajectory rocket to collide with it at the approaching solstice . The only known substance that can destroy strange matter is strange matter itself , so she is using the brain to discover a lightweight substitute . They return to the laboratory , and Faroon takes Mel to safety . The Rani returns , ready to take the Doctor to the brain , but he escapes into the Tetrap pit . She can ' t find him , but he is surrounded by Tetraps . Part three . The Doctor is able to escape from the Tetraps when Beyus feeds them . In the laboratory , the Doctor removes a part from the Rani ' s machine , then leaves , right before the Rani returns . She sounds an alarm . Meanwhile , Urak captures Mel , paralysing her with his venom . The Doctor meets Ikona , and narrowly escapes from one of the Rani ' s traps . A Tetrap is caught in it instead . Ikona shows the Doctor the Centre of Leisure and explains that his people have become indolent . The Rani , angry at Beyus ' lack of cooperation , turns on the globe in the Centre of Leisure , releasing killer insects . Faroon tells the Doctor that the Rani has Mel . The Rani offers a trade — the part he stole for Mel . However , when he makes the trade , Mel is revealed to be a hologram . The Doctor needs to get back to the laboratory to stop the Rani . He and Ikona try to bluff their way , but the Doctor is surrounded by Tetraps . The Rani feeds the Doctor ' s intellect into the brain , and it starts working , as the Doctor ' s brain suggests a new approach to the problem . Part four . To the Rani ' s annoyance , the brain starts spouting bad puns and nonsense . However , once disconnected , the Doctor inadvertently provides the brain with the means to determine the needed substance : Loyhargil . Upon impact , the strange matter would form a shell of chronon s around Lakertya , causing the brain to expand to fill the entire surface of the planet , converting it into a Time Manipulator . With this , the Rani can change the course of history and control the randomness of evolution throughout the universe . The Rani also casually mentions that she intends to leave the Doctor , Mel , the Lakertyans and the Tetraps to die on the planet during this process , but Urak overhears this , alarming him . The Lakertyan leader Beyus sacrifices his life to destroy the brain and delay the launch long enough for the rocket to miss the asteroid . The Rani escapes in her TARDIS , but finds it overrun with Tetraps who " invite " the Rani to accompany them to her homeworld . On Lakertya , the Doctor and Mel make their goodbyes with the people they had befriended and helped liberate from the Rani . The Doctor gives Ikona the antidote to the Rani ' s killer insects , but Ikona pours this away on the ground — explaining that his people must solve their own problems from now on if they are to survive . Before going into the TARDIS , Mel tells the Doctor that his new self is going to take some getting used to , to which he replies , " I ' ll grow on you , Mel , I ' ll grow on you . " Home video and audio releases . VHS releases . This story was released on VHS as follows :