The TARDIS is drawn to Vortis, where Barbara is lured out onto the planet's surface by an evil force called the Animus. The Animus has ravaged the surface of Vortis and taken control of its lower animal life, such as the giant ants called the Zarbi. The time travellers ally themselves with the exiled, butterfly-like Menoptra and the pitiable subterranean Optera, who seek to defeat the Animus and retake their planet.

Doctor Who's first season had firmly established the Daleks as a national phenomenon. As Season Two got under way the Doctor Who production team began contemplating the creation of a new monster to captivate viewers. Around the same time, Australian writer Bill Strutton -- who had contributed scripts for The Avengers and The Saint amongst other programmes -- met with producer Verity Lambert and outgoing story editor David Whitaker. Lambert noted that they wanted to develop a popular new monster different from the robot-like Daleks.

In response, Strutton recalled a childhood experience of being badly bitten when he interfered in a fight between two bull ants. His memories had been stirred by watching his own sons, aged six and four, fighting in a similar fashion. Strutton suggested that giant, venom-spraying ants might make an effective opponent for the Doctor. So impressed were Lambert and Whitaker by this idea that they decided to forego the usual request for a storyline from Strutton, and on September 28th, 1964, commissioned him to script a six-part serial entitled “The Webbed Planet”.

In constructing his episodes, Strutton had to ensure that Barbara was not needed for part three, to allow Jacqueline Hill a week's holiday. Apart from the word “Zarbi”, invented by Strutton's wife Marguerite, many of the names the author devised had biological origins. “Menoptra” (originally “Menoptera”) and “Optera” were both derived from lepidoptera, the name for the order of insects which includes butterflies. “Prapillus” (originally “Papillus”) and “Hilio” came from papilio, a Latin word for butterfly. The Carsenome (sometimes spelled “Carsinome”) took its name from “carcinoma”, referring to a (usually cancerous) tumour. “Animus” was another Latin term, literally meaning “angry spirit”.

Late in 1964, Whitaker's successor, Dennis Spooner, made some changes to Strutton's scripts. Originally, the Zarbi had the ability to spit venom, but Spooner instead created smaller, grub-like creatures to fulfill this function. These monsters, variously referred to as “Zarbi Guns”, “Zarbi Venom Guns”, “Zarbi Cannons”, “Zarbi Larvae” and “larvi guns”, were intended to be immature Zarbi. Spooner also took the opportunity to tie in Barbara's initial possession by the Animus with the preceding serial, his own The Romans, by making Barbara's gold bracelet a gift from Emperor Nero.

The director assigned to the Zarbi story, designated Serial N, was Richard Martin. Martin's most recent work had been on the similarly monster-centric The Dalek Invasion Of Earth, and he had also handled some episodes of the original The Daleks. It was Martin who decided that dancers should play the Menoptra. One performer under consideration was a young actor named Peter Purves, whom Martin felt was too talented to be relegated to the role of a Menoptra. Instead, Martin would eventually cast Purves as companion Steven Taylor in The Chase. Martin hired Australian mime Roslyn de Winter to choreograph the Menoptra; de Winter was also asked to develop the ornate speech patterns for the Menoptra and the Optera, as well as playing the central role of Vrestin.

Filming at the Ealing Television Film Studios began on January 4th, 1965, by which time the story's title had been amended slightly to The Web Planet. Unusually, Martin chose to portray the thin atmosphere of Vortis by placing a distorting lens on the camera, giving the appearance of shooting through a thin, petroleum jelly-like smear. Filming was intended to run until the 7th, with scenes involving acid and the Menoptra invasion of Vortis being the highlights of the schedule. However, both the reserve day on January 8th and extra time on the 11th were also needed due to the complexity of the recording; this would prove to be a sign of events to come.

Studio taping in Riverside 1 began on Friday, January 22nd; as usual, the remaining installments would be recorded there on the five following Fridays. By this time, it had been acknowledged that the cumbersome Zarbi costumes were not flexible enough to permit the monsters to be as agile as Strutton had originally envisaged. The action in some scenes was rearranged to accommodate this. On the 28th, Maureen O'Brien's contract was extended for fourteen more episodes, covering Serials P, Q and R.

The demanding nature of the serial started to take its toll on the production beginning the following week. The Zarbi required a 16-minute overrun, brought about by a variety of flubbed lines, missed cues, equipment problems, and troubles with the Zarbi costumes, one of which broke and had to be repaired. The week after, the start of recording on Escape To Danger was delayed when it was found that some of the sets had not been delivered to the studio, and the Carsenome floor had not been painted. Lighting and camera problems continued to plague the increasingly frazzled cast, and this time taping went 37 minutes beyond the schedule. This was the day during which one of the Zarbi operators, his vision impaired by his costume, ran right into the camera. So rushed was the recording, however, that this blooper was retained in the finished episode.

The next week, Lambert became frustrated with Martin, whom she felt was permitting his actors to make last-minute dialogue changes, many of which she suspected were due to the performers simply not remembering the correct lines. Lambert noted that major alterations should be confined to script readthroughs, and that any modifications made afterward should be made only with Spooner's involvement and approval. Although taping on the fourth and fifth installments proceeded without significant difficulties, the same was not true of The Centre, taped on February 26th. In this case, sound problems forced a 15-minute overrun before production of The Web Planet finally concluded.

It was around this time that William Russell decided to leave Doctor Who with the expiry of his contract, which encompassed three further serials. Russell felt his enthusiasm for the series had waned, and he was in need of a change. Hill, meanwhile, was surprised to learn that she would not be credited on Escape To Danger, the episode during which she had gone on vacation. This was contrary to the practise employed the previous season, when all the regular cast members were credited regardless of whether they actually appeared in a given broadcast. Hill protested this decision in the hope of seeing her credit restored when The Web Planet was sold for transmission overseas, but her request was ultimately denied.

Episode one of The Web Planet was watched by 13.5 million viewers, the most of any Doctor Who episode in the Sixties. Yet despite this milestone, and the production team's initial optimism for the Zarbi, their impractical design ensured that the monsters would not make a return appearance. The Web Planet also marked Strutton's lone contribution to Doctor Who; an unknown second idea, suggested to him by Verity Lambert, would go nowhere. In 1970, Strutton was commissioned to write a storyline for a four-part adventure called “The Mega” by then-script editor Terrance Dicks, but this went unused. A few years later, Strutton retired from writing. He died on November 23rd, 2003.

• Doctor Who: The Handbook: The First Doctor by David J Howe, Mark Stammers and Stephen James Walker (1994), Virgin Publishing, ISBN 0 426 20430 1.
• Doctor Who: The Sixties by David J Howe, Mark Stammers and Stephen James Walker (1992), Virgin Publishing, ISBN 1 85227 420 4.
• Doctor Who Magazine #286, 12th January 2000, “Archive: The Web Planet” by Andrew Pixley, Panini UK Ltd.
• Doctor Who Magazine Special Edition #7, 12th May 2004, “I'm Into Something Good” by Andrew Pixley, Panini Publishing Ltd.