Two spaceships collide in hyperspace, fusing the vessels together. Investigating the accident, the Doctor, Romana and K-9 meet Tryst, an eccentric scientist who is carrying samples of various planets within a machine called the Continuous Event Transmuter. The CET malfunctions, however, unleashing monstrous Mandrels onto both ships. Meanwhile, the time travellers discover that someone on board has been smuggling the illicit, addictive drug vraxoin -- and it becomes clear that the disastrous events are not unrelated.

Shortly after completing their Season Sixteen Doctor Who story The Armageddon Factor, Bob Baker and Dave Martin decided it was time to dissolve their decade-long writing partnership. Although was the end of Martin's association with Doctor Who, Baker continued to develop proposals for the programme. One of these was apparently called “Nightmare Of Evil”, and was submitted around New Year 1979. It dealt with the issue of drugs, which script editor Douglas Adams felt would make for a very original and relevant Doctor Who story. Baker had also designed his storyline to be very cost-effective, and this met the approval of producer Graham Williams. With the first two serials of Season Seventeen expected to be taxing on the budget, Williams was keen to make the fourth and fifth serials of the year as frugally as possible, in order to save money for the season finale.

Baker was commissioned to expand “Nightmare Of Evil” into full scripts on February 7th. The title was changed at this point to Nightmare Of Eden, as Adams felt that the original name was redundant. In addition to the narcotics element, Baker also found inspiration in the disaster movies which had become popular during the Seventies, such as The Poseidon Adventure, Airport and The Towering Inferno. Nightmare Of Eden was earmarked as Season Seventeen's fourth story in both the production and broadcast orders, and was assigned the production code Serial 5K.

The director booked for Nightmare Of Eden was Alan Bromly, was had previously helmed The Time Warrior in 1973. Bromly was now largely retired but still received occasional work from the BBC. Unfortunately, during rehearsals the old-school director quickly butted heads with Tom Baker, who was a commanding presence on Doctor Who and had become renowned for trying to impose his will on the production. Bromly had a very old-fashioned and authoritarian approach to directing, which did not sit well with the programme's star.

Also a source of concern during rehearsals was the drug element of the serial. Although Adams was a proponent of the angle, Williams was worried that it was unsuitable for a family-oriented show like Doctor Who, and his apprehension was shared by the series regulars. Lalla Ward, in particular, was keen to omit anything which might appear to glamourise the narcotics trade. As a result, various uses of drug language were amended to sound less appealing or exciting. Most notably, the drug at the centre of the story was originally called “xylophilin” or “XYP”, and nicknamed “zip”. This was changed to “vraxoin” (or “vrax” for short), although K-9's dialogue continued to refer to it by its original nomenclature.

Nightmare Of Eden was taped in two three-day blocks, both of which took place in BBC Television Centre Studio 6. Bromly had originally planned to record the serial more-or-less in story order, which was the traditional way of making Doctor Who until the mid-Seventies. However, he was ultimately convinced to proceed on a set-by-set basis, as had now become the norm. The recording of Nightmare Of Eden marked the return of David Brierly to Doctor Who as the voice of K-9: after making The Creature From The Pit at the start of the production schedule, Brierly had not been needed for either City Of Death or Destiny Of The Daleks.

The initial studio session for Nightmare Of Eden spanned August 12th to 14th. The first day dealt with scenes at the refreshment point and in the luggage section, as well as on the Empress bridge (for part one) and in the lounge (for parts one and two). Further bridge and lounge sequences were completed the next day, along with those in the Eden jungle and the capsule. August 14th was planned to be an effects-heavy day, involving scenes in the lounge which featured the CET projections, as well as the model shots of the Empress and the Hecate. Unfortunately, Bromly was ill-prepared for how extensively Doctor Who now incorporated special effects, and indeed for the generally faster pace of modern storytelling. Not all of the scheduled recording was completed, and the mood on set became strained.

The second studio block took place from August 26th to 28th. The first day was concerned with scenes in the passenger pallet and in the elevator area. The 27th was dedicated to various corridor sequences, in addition to those in the sick bay anteroom, the Empress power unit, and the dark room on the Hecate. Bromly made several changes to his recording schedule and was uncompromising in dictating how he wanted the actors to perform. This drew the ire of Tom Baker. He began vocally insulting his director, leading to an argument on the studio floor for which Williams had to be summoned to intervene.

The situation deteriorated completely on the final day of production. With Baker in open revolt, Bromly completed work on some further sequences in the corridors before informing Williams during the supper break that he was walking away from Nightmare Of Eden. Williams himself was forced to step in to direct the remaining material, which included scenes in the corridors and the elevator area. With blame for the debacle placed squarely on Bromly's shoulders, it was agreed that Williams would complete the post-production work on Nightmare Of Eden, and that Bromly would never again be invited back to Doctor Who. Bromly retired completely from television soon thereafter; he passed away in September 1995.

Nightmare Of Eden was also Bob Baker's final involvement with Doctor Who. He continued writing for programmes including Bergerac and also became script editor on shows like Shoestring and Into The Labyrinth. In the Nineties, Baker garnered acclaim for his work with stop-motion animator Nick Park on the Wallace & Gromit series, which included the Academy Award-winning 2005 feature film Wallace & Gromit in The Curse Of The Were-Rabbit. Since the late Nineties, Baker has also been attempting to spin his cocreation, K-9, into his own television series. The project took on new life with the success of Doctor Who's 2005 revival, and is now planned for broadcast in 2008.

Meanwhile, the unpleasantness he had had to contend with on Nightmare Of Eden helped Williams make up his mind to leave Doctor Who at the end of Season Seventeen. Williams had endured three punishing years on the programme, and he had finally had enough.

• Doctor Who: The Handbook: The Fourth Doctor by David J Howe, Mark Stammers and Stephen James Walker (1992), Virgin Publishing, ISBN 0 426 20369 8.
• Doctor Who: The Seventies by David J Howe, Mark Stammers and Stephen James Walker (1994), Virgin Publishing, ISBN 1 85227 444 1.
• Doctor Who Magazine #273, 13th January 1999, “Archive: Nightmare Of Eden” by Andrew Pixley, Marvel Comics UK Ltd.
• Doctor Who Magazine Special Edition #9, 22nd December 2004, “One Step Beyond” by Andrew Pixley, Panini Publishing Ltd.
• In-Vision #42, March 1993, “Production” edited by Justin Richards and Peter Anghelides, Cybermark Services.