The TARDIS is catapulted into a parallel universe where Rose discovers that her father, Pete, is still alive. A successful but childless man in this reality, Peter Tyler is in business with the wealthy and powerful John Lumic, the owner of Cybus Industries, who is seeking to stave off his terminal illness by any means necessary. At the same time, Mickey learns that his counterpart, Ricky, is the leader of the Preachers, a resistance movement trying to prevent Lumic from giving humanity the ultimate upgrade. Much to the Doctor's horror, Lumic's plan is one which he has seen executed before: the creation of the Cybermen!

Early in 2005, Billie Piper informed executive producer Russell T Davies that she would not be remaining on Doctor Who beyond her second season. Although she had loved her time playing companion Rose Tyler, Piper felt that two years as a regular on the demanding show would be enough, and she was concerned that staying too long would risk stifling her now-incandescent acting career. Davies therefore made Rose Tyler's exit a keystone of Season Twenty-Eight. He immediately ruled out the option of killing the character, which he thought would fly in the face of Doctor Who's optimistic outlook. Instead, he would create a situation in which Rose became irrevocably separated from the Doctor -- an event which he felt was the only believable way to shatter the strong bond which had developed between the characters.

To this end, Davies decided to draw upon 1970's Inferno, which had established the existence in Doctor Who of parallel universes -- worlds where history diverged from that of the normal timeline in which most of the programme's events were presumed to take place. Davies hit on the idea of setting up such an alternative Earth early in the 2006 season, and then revisiting it in the finale -- ultimately Army Of Ghosts / Doomsday -- which would culminate in Rose becoming trapped there.

Mickey Smith would conclude his evolution from quivering coward to true hero

Inferno had also included evil doppelgangers of the Doctor's allies Liz Shaw, Brigadier Lethbridge Stewart and Sergeant Benton. Davies was eager to attempt a similarly disparate take on some of the programme's current roster of recurring characters. In particular, he felt that a confrontation between Mickey Smith and his parallel-world counterpart could be the vehicle through which to conclude his evolution from the quivering coward of 2005's Rose into a true hero. Davies also acted quickly to ensure that Shaun Dingwall would be interested in reprising his role as Pete Tyler -- Rose's late father, originally seen during 2005 in Father's Day -- and approached him at the Doctor Who launch party on March 8th.

Meanwhile, Davies was contemplating the return of the Cybermen to Doctor Who. Season Twenty-Seven had resurrected the Daleks to popular acclaim, and Davies now wanted to do the same for the show's second-most famous monsters. For the reintroduction of the Daleks, he had sought inspiration in the range of Doctor Who audio dramas from Big Finish Productions, and he wanted to repeat the experiment with the Cybermen. Davies was impressed with Spare Parts, a 2002 Fifth Doctor story written by Marc Platt, who had contributed to televised Doctor Who back in 1989 with Ghost Light. A prequel to 1966's The Tenth Planet, the very first Cyberman story, Spare Parts explored their heretofore-unrevealed creation in what was essentially a character piece, examining the conditions which drove the citizens of the planet Mondas to allow themselves to be adapted into such creatures. It included such elements as a woman converted into a Cyberman who, horrifyingly, began to regain her humanity.

However, Davies was wary of what he saw as a complex continuity surrounding the Cybermen. He therefore elected to introduce a new version of the monsters in the parallel universe he was developing; consequently, while he intended to make use of some of the ideas and themes of Spare Parts, he did not plan to adapt the play to any significant extent. Davies' initial impression of the alternate universe had a steampunk bent, with clockwork Cybermen created in response to a disease which was ravaging humanity. The 2005 animated film Robots gave Davies the idea that the Cyber Controller should be able to extrude a variety of metal weapons.

“Parallel World” was envisaged as a two-part story which would air fourth and fifth in the 2006 schedule. When Tooth And Claw was later added to the season, the two episodes were pushed back to the fifth and sixth positions. Davies felt that, as with the mid-season placement of Dalek in 2005, the appearance of the Cybermen would provide a boost to Doctor Who's publicity partly through its run. To develop the scripts, Davies recommended his friend Tom MacRae. The writer accepted the assignment in early April, and the forthcoming return of the Cybermen was announced in the pages of Doctor Who Magazine on May 26th.

The Cybermen were reimagined as the natural extension of society's obsession with “upgrading” personal technology

MacRae initially hewed fairly closely to Spare Parts by setting his serial on a dying Earth, where the Cybermen came into existence when efforts to save humanity from a terrible plague were taken to extreme lengths. However, Davies was concerned that this approach was effectively still rooted in mid-Sixties anxiety about body part replacement -- the paranoia which had originally inspired the Cybermen, but was now outdated. Instead, he and MacRae worked together to reimagine the Cybermen as the natural extension of a modern phenomenon: society's obsession with constantly “upgrading” personal technology. The Cybermen would now represent the ultimate upgrade of the human mind: the transplantation of the brain into a resilient artificial body. Indeed, MacRae wanted to lay the groundwork for this outcome by suggesting that the people of the parallel Earth regularly augmented their organs in “body shops” run by Cybus Industries. Davies found this scenario less than credible, however, and it was abandoned.

With the direction for “Parallel World” now set, MacRae continued developing his scripts. One of his key characters was originally a young businessman named Jacob Lumic, who had replaced some of his body parts with cybernetic attachments as part of his quest to save humanity from a deadly disease. With the global pandemic eliminated due to the altered conception of the Cybermen, Lumic's new motivation was to cure his dying father. Finally, the son's role was essentially taken over by Mr Crane, while the older man was now terminally-ill businessman John Lumic. An additional Preacher was Esme, a hard-bitten former Green Beret. This character survived to the audition stage; one of the actresses who read for the part was Freema Agyeman, who would later be cast as companion Martha Jones. However, Esme was dropped when it was felt that her presence made the Preachers seem too capable, as opposed to a group of well-intentioned amateurs who were out of their depth.

In early drafts, the Jackie Tyler Cyberman died at Rose's hands, while the Cyberman with the broken emotional inhibitor was an eleven-year-old boy. MacRae envisaged the counterparts of Mickey, Jackie and Pete as diverging far more from their familiar portrayals, but Davies encouraged him to scale this back. Pete's codename was originally “Puck”, in reference to the mischievous fairy best known as a character in William Shakespeare's A Midsummer Night's Dream. It then became “Janus”, after the two-faced god of beginnings and endings in Roman mythology. His eventual sobriquet, “Gemini”, was the Latin word for “twins”, most commonly used in reference to the Greco-Roman gods Castor and Pollux. The time rotor of the TARDIS was shattered at the start of the story, an effect ruled out on the grounds of cost. A nod was made to the original Cybermen, with Crane's van bearing the logo of International Electromatics -- the company which aided the Cybermen in the 1968 serial The Invasion.

Originally, the link to the other universe was just sufficient to allow the Doctor to take “his” Jackie there

The climactic action resulting in the destruction of the Cyber Controller took place in a lift rather than on the Cyber Factory roof, with the transformed Lumic trying to break through the compartment's floor. At the end of the story, the link between the TARDIS and the other universe was just sufficient to allow the Doctor to take “his” Jackie there, to be united with the “other” Pete, while Rose elected to continue travelling in the TARDIS. However, Davies subsequently concluded that it was too depressing to confront Rose with such a choice at this stage of the season, especially given that the parallel world would be revisited in Army Of Ghosts / Doomsday.

Whereas the look of the Daleks was largely inflexible, Davies had far greater latitude with the Cybermen, not least because they had already evolved considerably over the course of their appearances between 1966 and 1988. As design drawings were developed for the new Cybermen, Davies was particularly adamant that they should eschew the “silver giant” label often applied to the monsters in the past; viewing silver as a flimsy material, he preferred to think of the Cybermen as made of steel. On the other hand, Davies was eager to retain certain elements from previous Cyberman designs -- particularly the handlebar ears and the teardrop eyes. An Art Deco aesthetic was agreed upon, inspired in part by the 1927 science-fiction classic Metropolis and the Hoover Building in Perivale, London, which opened in 1933. Although some thought was given to keeping the traditional chest unit, MacRae suggested replacing it with a stylised Cybus Industries logo.

By the end of October, the first half of “Parallel World” had been renamed Rise Of The Cybermen; the second installment would later be given the title The Age Of Steel. Both episodes formed part of an ambitious production block which also included Army Of Ghosts / Doomsday -- the longest yet attempted since Doctor Who's revival. These were the lone episodes to feature Pete and the Cybermen, and the last which required Noel Clarke as Mickey. They were assigned to veteran director Graeme Harper, who had made 1984's The Caves Of Androzani and 1985's Revelation Of The Daleks. Harper had contacted Davies upon the announcement of Doctor Who's return in September 2003 to indicate his interest in returning to the show, although prior commitments had precluded his involvement in the 2005 season.

As John Lumic, Harper cast Roger Lloyd Pack, who was eager to play the villain in the manner of Donald Rumsfeld, the United States Secretary of Defense who was one of the chief architects of the 2003 Iraq War. Shortly before filming began, Lloyd Pack broke his ankle in a fall down a flight of stairs. Fortunately, the Lumic role had already been scripted as being entirely wheelchair-bound, meaning that Lloyd Pack's injury would not interfere with his performance.

Work on Rise Of The Cybermen / The Age Of Steel began with a day in London on November 1st

Work on Rise Of The Cybermen / The Age Of Steel began with a day in London on November 1st. The principal venue was Lambeth Pier on the Albert Embankment in Lambeth, for the scenes in which the Doctor, Rose and Mickey first explored the parallel Earth. Footage was also captured of the Battersea Power Station at Nine Elms and Thames House, the Westminster headquarters of MI5. Harper discovered some unused helicopter footage of the city which had been recorded for 2005's Aliens Of London / World War Three, meaning that he could save the expense of another flyover for the Cyberman tale.

Returning to Wales, the cast and crew spent November 3rd at Talygarn Manor near Pontyclun, a former rehabilitation centre which now served as the Preachers' hideout. The next day, Mr Crane approached the homeless people near the Cardiff Docks. November 7th was spent at the regular Doctor Who studio space of Unit Q2 in Newport, concentrating on material in the TARDIS. On the 8th, it was planned to complete the Thames sequences at the Riverfront Arts Centre in Newport, but rain forced Harper to postpone most of his schedule. Recording resumed on November 9th and 10th at Unit Q2, this time for scenes aboard Lumic's zeppelin. More delays arose on the 11th, when Uskmouth Power Station in Newport doubled for Battersea. It was thought that Uskmouth could be shut down for six hours to allow the crew to film, but an unseasonable cold snap -- and the resulting increased power demand -- made this impossible. Harper was again forced to adjust his plans.

On November 14th, the scenes on the power station roof were actually recorded on the ground, at the Cardiff Heliport's Veritair Limited tarmac on Cardiff Bay. The next day, the disused Ely Paper Mill in Cardiff provided the Cyber Factory stairs, while street scenes were also taped in its vicinity. On November 16th, the outstanding Thames material was finally completed at the Riverside Theatre in Newport.

A major venue for Rise Of The Cybermen / The Age Of Steel was Coedarhydyglyn, a private residence in St Nicholas, which served as the Tyler estate. Harper's team was at work there on November 17th and 18th, and then returned after the weekend from the 20th to the 23rd. Filming on the 24th began back at the Veritair tarmac, this time capturing the disembarkation from the President's zeppelin. Harper had then intended to record the scene involving the Cyberman with the malfunctioning emotional inhibitor, at Victoria Park Playground in Cardiff. At this stage, the woman was called Kerry rather than Sally, and the encounter took place during the journey to Battersea, which meant that it also featured Rose, Mickey, Pete and Jake. However, snowy weather prompted yet another change of plans, and cast and crew instead returned to Coedarhydyglyn for more sequences at the Tyler mansion.

Scenes in the Cyber Factory control room and cooling tunnels were filmed at the Unit G12 studio facility in Treforest on November 25th and 26th. This included the revised scene featuring the Sally Cyberman, repositioned in the narrative to take place as the Doctor and Mrs Moore exited the tunnels. The change also gave Davies the opportunity to delay Mrs Moore's death -- which originally happened at this point -- since the character and actress Helen Griffin had proved popular with the crew. Work on the two episodes then became much more sporadic as the production largely shifted focus to Army Of Ghosts / Doomsday. November 28th was spent in Cardiff, with Ricky's gran's house found on Compton Street, while the exterior of the Preachers' headquarters was the decommissioned Royal Hamadryad Hospital.

More Cardiff filming on December 5th saw a variety of streets involved as the Doctor and his friends evaded the Cybermen, while Grangemoor Park was the venue from which the Doctor and his party spied on Battersea Power Station. Briefly playing a Cyberman on this day was Blue Peter presenter Gethin Jones, who was taping a segment for the children's programme. More material in the cooling tunnels was recorded on the 6th, this time at Brackla Bunkers in Bridgend. On December 15th, Mickey and Ricky were pursued by the Cybermen near Sovereign House in Newport. More of this material was filmed the following day at the Newport Docks, culminating in Ricky's death; the intention had been to leave the viewers uncertain as to which of the doppelgangers had actually perished. The 16th also saw the footage for Pete's advertising poster captured at Unit Q2.

Work then resumed in 2006, albeit a day later than anticipated. Harper had intended to spend January 6th filming scenes in the conversion and corridor areas of the Cyber Factory, only to be informed a couple of weeks earlier that the planned location was no longer available. Instead, the next recording for Rise Of The Cybermen / The Age Of Steel took place on the 7th at Mount Stuart Square in Cardiff Bay, where the Doctor and Rose observed the “Daily Download”. The sequences originally scheduled for January 6th finally went ahead on the 11th, at the Stella Artois brewery in Wilcrick. On January 12th, the Doctor and his friends hid from the Cybermen at Womanby Street in Cardiff. The next day, the remainder of the material on the Cyber Factory roof was filmed at RAF St Athan in the Vale of Glamorgan. The scene in the Tylers' flat was then taped at Unit Q2 on January 18th.

Russell T Davies wrote a new pre-credits sequence involving John Lumic and Dr Kendrick

This should have completed work on Rise Of The Cybermen / The Age Of Steel, but Davies had become unhappy with the first episode's pre-credits sequence, which spanned the TARDIS scene through to Rose finding the Vitex advertisement. He wanted to hint at the nature of the reimagined Cybermen earlier, and so he wrote additional material involving Lumic and a new character, a scientist named Dr Kendrick. This sequence was recorded on February 18th on the premises of Gwinnut Ltd Electrical Engineers in Cardiff. Pick-up shots of Kendrick were captured at Unit Q2 on February 22nd. Another late addition was the newsreader, and this footage was taped at Unit Q2 on March 9th alongside various inserts.

The only significant edit made to the story was the deletion of a line confirming that Ricky and Jake had been lovers, as part of a sequence in which Mickey vowed not to try to take his counterpart's place. Executive producer Julie Gardner and producer Phil Collinson were both concerned that no groundwork had been laid to suggest a romantic relationship between the two characters.

Meanwhile, the TARDISodes for both episodes had been written by Gareth Roberts. Unlike earlier installments of the online series, they principally relied on footage shot for the story itself rather than on specially-filmed material. Nonetheless, Noel Clarke did record a brief appearance as Ricky in an alley off Newport Road in Cardiff on February 1st. The TARDISode for Rise Of The Cybermen, fifty-three seconds in length, took the form of a message from Gemini to the Preachers about the Ultimate Upgrade program, eventually interrupted by an advertisement from Cybus Industries. Its forty-two-second counterpart for The Age Of Steel consisted of Lumic's order to his worldwide Cyber Factories to implement the Ultimate Upgrade initiative. As usual, each was released one week prior to the broadcast of the corresponding episode.

Rise Of The Cybermen was transmitted on May 13th. Although scheduled for 7.00pm, it wound up being delayed by twenty-three minutes when the FA Cup Final between Liverpool and West Ham, televised earlier in the day, went to penalties. A week later, on May 20th, The Age Of Steel was brought forward to 6.45pm to accommodate the annual Eurovision Song Contest later in the night. As a result, instead of its usual lead-in of Strictly Dance Fever, Doctor Who was preceded on this occasion by the quiz show Weakest Link: All Singing, All Dancing Special.

• Doctor Who Magazine Special Edition #14, 9th November 2006, “Episodes 5 & 6: Rise Of The Cybermen / The Age Of Steel” by Andrew Pixley, Panini Publishing Ltd.
• Doctor Who: The Complete History #52, 2016, “Story 172: Rise Of The Cybermen / The Age Of Steel”, edited by John Ainsworth, Hachette Partworks Ltd.
• Doctor Who: The Inside Story by Gary Russell (2006), BBC Books.