from tardi wiki   was the eighth and final episode of Series 15 of Doctor Who. It premiered on 31 May 2025. The story featured the return of Omega in an active role as an antagonist for the first time since the Fifth Doctor story Arc of Infinity [+], now voiced by Nicholas Briggs, with this story revealing Omega's time spent trapped in the Under-Universe had physically altered and deformed him into a monstrous corpse like being. The story also shows the apparent fate of the bi-generated Rani at Omega's hands, while the Mrs Flood incarnation of the Rani escapes shortly after witnessing her successor's apparent demise. The Rani reveals how she survived the Spy Master's genocide of Gallifrey, and that the genetic explosion caused by the Spy Master had rendered any surviving Time Lords and Time Ladies completely sterile, which was why she enacted her plan to find Omega in order to save their race, though with the purpose of creating a new Gallifrey she could rule over. In addition, her ability to follow the Doctor throughout time and space is revealed to be accomplished by use of a Time Ring rather than a TARDIS. Steph de Whalley also returns as Anita Benn, where it's revealed she began working in the Time Hotel after Joy to the World [+] and had been looking for the Fifteenth Doctor, in doing so archive footage from The Wedding of River Song [+] and Day of the Daleks [+] respectfully would be used to have Anita see the Eleventh and Third Doctors when visiting the events of those stories, before archive footage of Rogue [+] is used when Anita finds an early version of the Fifteenth Doctor during the events of that story. Before departing, Anita would mention "the Boss" who was previously mentioned by Beep the Meep in The Star Beast [+]. In addition to the Doctor's previous incarnations appearing through archive footage, Jodie Whittaker makes a surprise appearance as the Thirteenth Doctor near the end of this story, marking her first appearance since The Power of the Doctor [+]. Most notably, this story was the final chronological appearance of Ncuti Gatwa as the Fifteenth Doctor, with the story ending with his regeneration, caused by him sacrificing his current incarnation in order to bring Poppy back into existence, the Doctor's regeneration in this story was also the first time since The Parting of the Ways [+] in 2005 that the Doctor had regenerated at the end of the current series; in the revived run of the series, starting from The End of Time [+] up to The Giggle [+], the Doctor would be seen regenerating in either Christmas or New Year's specials set in between numbered series. In a twist however, The Reality War and the Fifteenth Doctor's regeneration would end with Billie Piper, having previously portrayed Ninth and Tenth Doctor companion Rose Tyler, being introduced in the final moments of the story, and with her role being left uncredited. The Doctor - Ncuti Gatwa The Doctor - Jodie Whittaker Belinda Chandra - Varada Sethu Ruby Sunday - Millie Gibson The Rani - Archie Panjabi Mrs Flood - Anita Dobson Anita Benn - Steph de Whalley Winnie Petheridge - Sam Lawton Shirley Bingham - Ruth Madeley Carla Sunday - Michelle Greenidge Conrad Clark - Jonah Hauer-King Poppy - Sienna-Robyn Mavanga-Phipps Kate Stewart - Jemma Redgrave Susan Triad - Susan Twist Christofer Ibrahim - Alexander Devrient The Vlinx - Aidan Cook Rose Noble - Yasmin Finney Melanie Bush - Bonnie Langford Cherry Sunday - Angela Wynter Voice of Omega / The Vlinx / Dalek - Nicholas Briggs Lakshmi Chandra - Nila Aalia And introducing Billie Piper Uncredited First Doctor - William Hartnell (archive footage) Second Doctor - Patrick Troughton (archive footage) Fourth Doctor - Tom Baker (archive footage) Fifth Doctor - Peter Davison (archive footage) Sixth Doctor - Colin Baker (archive footage) Seventh Doctor - Sylvester McCoy (archive footage) Guardian of the Edge - Paul McGann (archive footage) War Doctor - John Hurt (archive footage) Ninth Doctor - Christopher Eccleston (archive footage) Tenth Doctor / Fourteenth Doctor - David Tennant (archive footage) Twelfth Doctor - Peter Capaldi (archive footage) Fugitive Doctor - Jo Martin (archive footage) Crew To be added... Worldbuilding Omega and the Rani The Doctor reveals that Omega is viewed as the Original Sin of the Time Lords who has discovered time travel. He was cast out from Gallifrey because he was insane. Omega has two hearts like all Time Lords. The Underverse is a world of legends, causing Omega to change into the Mad God Titan and become his own legend. After his escape, Omega wanted to become the God of Time and feast upon Time Lords. He also immediately recognises the Doctor. The Rani has her own Time Ring and Sonic Screwdriver. The Mrs. Flood Rani later escapes with the Time Ring. UNIT Susan Triad has build her own Zero Room at UNIT floor minus 10 to use as an escape pod. UNIT can also fight using Parallax Cannons. There are a few glitches in the new world: the border between Norway and Sweden has moved seven miles east. The colour teal is more blue and actor Ernest Borgnine is still alive. Belinda and her family Belinda mentions she has an uncle named Roo living in Kerala. Her mother's name is Lakshmi. She plays a concert in Manchester. Belinda wanted to see the planet Neptune and the Big Bang before departing from the Doctor. Belinda makes the Doctor an uncle to Poppy. She reveals she met Poppy's real father when she was 21 and is named Ritchie Akingbola, though they are separated. Ruby and her family Ruby mentions that during their time together, Conrad never revealed who his father is. Cherry reveals that she likes to play poker and that Joseph is the name of her late husband. The Doctor and the TARDIS The Fifteenth Doctor mentions he can turn the TARDIS into anything. The Doctor has never been to Kerala. He also reveals that in the year 60,000, there is a planet called New New Delhi. The Fifteenth Doctor can punch regeneration energy from his hands into the Time Vortex to alter reality. However this causes him to regenerate. He can still stall the regeneration itself for a short time. The Thirteenth Doctor is unaware of what bi-generation is. The Thirteenth Doctor mentions the TARDIS having "a third strand of phenotype markers that can turn a micro-spasm". Both Doctors hope that they will always wish they had more time before regenerating. The TARDIS remembers the Fugitive Doctor, revealing her on the TARDIS console screen between the Fourteenth and Fifteenth Doctors. The Fifteenth Doctor is surprised to see the Thirteenth, joking that "normally the other guy shows up". References The Doctor gives The Upside Down from Stranger Things and Narnia as examples about the world hidden below, or "the Underverse". Notes Jodie Whittaker revealed that one of her regrets from her tenure was that she didn't get to interact with Peter Capaldi or David Tennant during the regeneration handovers, as their scenes were filmed separately. So getting to interact with Ncuti Gatwa during his own regeneration handover was special and a highlight of coming back for her cameo. A promotional image of the Doctor and Belinda dancing with a "Happy May Day" banner in the background was released for the episode, but no such scene exists in the final episode. Jodie Whittaker wore a wig for her cameo, as she had long brown hair at the time. Russell T Davies revealed that Jodie Whittaker's codename onset was "Petrol", because he might use it as a companion name in the future. This two-parter formed Block Five of Series 15.