The Sisterhood of Karn tends a sacred flame, which provides an elixir granting eternal life and which is used by the Time Lords to aid in regenerative crises. The TARDIS arrives on Karn at a time when the sacred flame is dying, and the Sisterhood accuses the Doctor of planning to steal the last vestiges of the elixir. But also on Karn is the mad neurosurgeon Mehendri Solon. He hides the brain of Morbius, an evil Time Lord thought to have been executed. Solon is trying to build a new body for Morbius, and is lacking only a suitable head... the head of a Time Lord.

One of the topics that producer Philip Hinchcliffe wanted to explore in Doctor Who was robotics. Although Robot -- the serial written by former script editor Terrance Dicks to introduce Tom Baker's Fourth Doctor -- had already touched on this subject, Hinchcliffe wanted to delve into the relationship between man and machine, having been intrigued by the works of science-fiction author Isaac Asimov. Dicks, meanwhile, had stayed in close contact with the Doctor Who production office. With Hinchcliffe and new script editor Robert Holmes eager to use gothic horror staples as a source for story ideas, he had developed a vampire adventure called “The Haunting”. When this project fell through in early 1975, he and Holmes instead began discussing ways to bring Hinchcliffe's robotics idea to life.

Still thinking in terms of gothic horror, the pair decided to draw upon one of the genre's foundational works: Mary Shelley's 1818 novel Frankenstein, or The Modern Prometheus. The story of a scientist who brought to life a man assembled from corpses, its twentieth-century popularity had come about when Universal Pictures released James Whale's Frankenstein on the silver screen in 1931. In the UK, Hammer Films had also made a successful series of movies starring Shelley's monster, beginning with 1957's The Curse Of Frankenstein. These discussions led to the development of a storyline entitled The Brain of Morbius, for which Dicks was commissioned on May 1st.

The Frankenstein elements reflected Robert Holmes' tendency to base adventures on classic works of gothic horror

Dicks' idea concerned a space criminal called Morbius -- likely named after the troubled scientist in the 1956 feature film Forbidden Planet, which had already inspired Planet Of Evil earlier in Season Thirteen -- who was catastrophically injured after crashlanding on a planet. His robot servant rescued his brain and sought to restore Morbius to life. However, the robot lacked any sense of aesthetics, and assembled a patchwork body for the vainglorious Morbius by scavenging parts from the corpses of various aliens, despite their vastly differing physiognomies.

Dicks was commissioned to turn The Brain Of Morbius into full scripts on June 6th, and completed his work just before heading overseas on holiday in early August. Several elements were lifted from his 1974 stage play Doctor Who And The Daleks in The Seven Keys To Doomsday. The crab-like elements of Morbius' new body were suggested by the Clawrantulars, monsters who served the Daleks in the theatrical script. Similarly, both stories were set on the planet Karn, which had been the home of a decayed civilisation in the stage play, and saw the Doctor engaged in a mental duel. Meanwhile, the Sisterhood of Karn was inspired by the immortal Ayesha, the title character of H Rider Haggard's 1887 novel She: A History Of Adventure.

A key requirement imposed by the production team arose from the serial's budget. It was intended that The Brain Of Morbius would be the penultimate adventure of Doctor Who's thirteenth season, and it was anticipated that the finale would be expensive. As such, Dicks was asked to ensure that no filming -- location, model, or otherwise -- would be needed for The Brain Of Morbius, making it the first completely studio-bound Doctor Who serial. However, as they reviewed Dicks' scripts, Hinchcliffe and Holmes concluded that Morbius' robot servant could not be effectively realised without vastly overspending. They were also concerned that Dicks had veered too far away from the desired horror flavour. When Dicks returned from his holiday, there was little time left before the start of production, and so the writer gave Holmes carte blanche to restructure his scripts.

Holmes eliminated the primary issue by replacing Dicks' robot with a mad scientist named Solon. He added Condo, a hulking servant, as an homage to the deformed sidekick often paired with cinematic versions of Frankenstein starting with Fritz in the Universal Frankenstein. Retaining the mental duel between the Doctor and Morbius, Holmes controversially included faces whom he intended to be incarnations preceding the first televised Doctor, William Hartnell. Apparently contradicting 1972's The Three Doctors, which had established Hartnell's version as the original Doctor, this scene would spawn many attempted explanations in Doctor Who spin-off media and fan writings, before finally being resolved by The Timeless Children in 2020.

Terrance Dicks was very unhappy with the degree to which Robert Holmes had rewritten The Brain Of Morbius

Unfortunately, upon receiving the revised scripts for The Brain Of Morbius on September 15th, Dicks was very unhappy with the degree of rewriting Holmes had performed. Although he came to understand why the production team had made such substantial changes, Dicks nonetheless felt that the removal of the robot character undermined the story's central ideas. A few days later, Dicks met with Hinchcliffe and Holmes to discuss the situation, and it was suggested that The Brain Of Morbius might instead be credited to Holmes, or to the “Stephen Harris” pseudonym recently applied to Pyramids Of Mars. Finally, on September 22nd, Dicks wrote Holmes to ask that the script editor “devise some bland pseudonym” for use on The Brain Of Morbius; much to Dicks' amusement, Holmes duly attributed the serial to “Robin Bland”.

The director assigned to The Brain Of Morbius was Christopher Barry, whose last Doctor Who work had been on Robot. Inspired by the Frankenstein trappings of the serial, Barry considered casting horror icons such as Vincent Price (House Of Wax, The Abominable Dr Phibes) and Hammer regular Peter Cushing (who had also starred in two film versions of Doctor Who during the Sixties) in the role of Solon. The role ultimately went to Philip Madoc. Thanks to the lack of pre-filming for The Brain Of Morbius, Tom Baker and Elisabeth Sladen effectively enjoyed a month off after completing The Android Invasion at the end of August. This was very welcome, given that the decision to make Doctor Who's twelfth and thirteenth seasons back-to-back meant that the series stars had been in production for eleven consecutive months, dating back to The Sontaran Experiment.

The Brain Of Morbius was made in a pair of two-day studio blocks, held on Mondays and Tuesdays. The first session took place on October 6th and 7th at BBC Television Centre Studio 1 in White City, London. Most of Episode One was taped on the Monday, alongside material set amidst the rocky wastelands of Karn. The Tuesday saw the rest of Episode One recorded -- picking up from Sarah spilling her wine -- in addition to the initial laboratory scene and the majority of Episode Two.

On October 20th and 21st, the second recording block took place in TC3. The Monday principally dealt with Episode Three, although Barry's schedule also encompassed the sequence between Solon and Condo from the start of Episode Two, as well as the chandelier smashing in Episode One and material with the wounded Condo in the gallery for Episode Four. In addition to the remaining Episode Four material, the Tuesday also involved the completion of the last few scenes of the preceding installment, as well as the sacrificial bonfire for Episode Two.

Members of the crew were pressed into service as the Doctor's previously unseen earlier incarnations

It was on October 21st that Barry recorded the mental duel between the Doctor and Morbius. Hinchcliffe had originally planned to photograph well-known actors as the Doctor's earlier incarnations, but he was unable to find suitable candidates. A request for volunteers amongst those working at Television Centre secured only the participation of Chris Baker, a production assistant who had been newly elevated to director, and who was working down the hall from the Doctor Who production office. Alongside Baker, crewmembers for both The Brain Of Morbius and The Seeds Of Doom -- the next serial in production -- were dressed in period garb and pressed into service. They included Hinchcliffe, Holmes, Barry, The Seeds Of Doom director Douglas Camfield, its writer Robert Banks Stewart, and production manager George Gallaccio. A shot of production assistant Graeme Harper, taken during the making of 1971's Colony In Space and in which he was dressed in the Adjudicator outfit worn by Roger Delgado, was also repurposed. Meanwhile, the images of Jon Pertwee and Patrick Troughton both came from The Three Doctors, while William Hartnell was represented by a photograph from 1965's The Space Museum.

Production on The Brain Of Morbius then concluded with a remount of two scenes originally taped on October 21st. These were likely the Episode Four sequences in which Morbius attacked Solon in his laboratory, and Solon's subsequent recovery. This additional recording took place on October 24th, in an unknown studio at BBC Television Centre.

Episode One of The Brain Of Morbius was originally scheduled for broadcast on December 20th, one week after the concluding installment of The Android Invasion. Ultimately, however, it was decided that Doctor Who should take a two-week break during the Christmas period, delaying the opening episode until January 3rd, 1976. With The Basil Brush Show and Bruce Forsyth And The Generation Game having both concluded their runs, Doctor Who was now preceded by Walt Disney's The Mouse Factory and a news update, and followed by It's Cliff -- And Friends. Episodes One and Four were both delayed by ten minutes, to 5.55pm, in order to accommodate the inclusion of the FA Cup Draw during Grandstand.

Mary Whitehouse, president of the National Viewers' and Listeners' Association, had renewed her years-old attacks on Doctor Who during 1975. Now The Brain Of Morbius saw Whitehouse once again condemning the programme as being overtly horrific. In a letter to Sir Michael Swann, the Chairman of the BBC, she pointedly demanded the rescheduling of Doctor Who to much later in the evening. The British press was beginning to take notice...

• Doctor Who Magazine #329, 30th April 2003, “Archive: The Brain Of Morbius” by Andrew Pixley, Panini Publishing Ltd.
• Doctor Who Magazine #564, June 2021, “The Timeless Doctor” by Stuart Humphryes, Panini UK Ltd.
• Doctor Who Magazine Special Edition #8, 1st September 2004, “Bohemian Rhapsody” by Andrew Pixley, Panini Publishing Ltd.
• Doctor Who: The Complete History #24, 2016, “Story 84: The Brain Of Morbius”, edited by Mark Wright, Hachette Partworks Ltd.
• Doctor Who: The Handbook: The Fourth Doctor by David J Howe, Mark Stammers and Stephen James Walker (1992), Virgin Publishing.
• Doctor Who: The Seventies by David J Howe, Mark Stammers and Stephen James Walker (1994), Virgin Publishing.
• In·Vision #12, January 1989, “Production” edited by Justin Richards and Peter Anghelides, Cybermark Services.