Having left Amy and Rory behind for their own safety, the Doctor must soon face his death at Lake Silencio -- but first, there's an old friend he wants to visit. Craig Owens is now a father, struggling to care for baby Alfie while his wife, Sophie, is away. As a result, he's oblivious to the strange events unfolding around him. People are going missing, unexplained electrical surges plague the neighbourhood, and a mysterious silver rat stalks the local shopping mall. Before long, the Doctor and Craig uncover a teleport relay which connects an out-of-order lift to a Cyberman spaceship. But is this an invasion, or something else?

Since Doctor Who's return to television in 2005, each season had concluded with a two-part finale. For Season Thirty-Two, however, executive producer Steven Moffat instituted a number of changes to the Doctor Who format, one of which was to end the year with a single-episode story: The Wedding Of River Song. The year's penultimate adventure would instead serve as something of a thematic prelude -- a “calm before the storm” in which the Doctor, preparing to face his apparently imminent demise, enjoyed a brief holiday by visiting an old friend. This would be Craig Owens, who was introduced in Gareth Roberts's The Lodger during Season Thirty-One. Moffat had been delighted with that episode's reception, and he quickly checked on the interest and availability of actor James Corden to return to the role.

On July 8th, 2010, Moffat offered Roberts the opportunity to write a sequel, for which a storyline was prepared by mid-September. Keen for the Doctor and Craig's escapades to continue taking place in a mundane, everyday environment, Roberts considered settings such as a hospital, a police station and a supermarket before finally settling on a department store. The involvement of Craig's wife, Sophie, would have to be limited, due to actress Daisy Haggard's commitments to the play Becky Shaw. Similarly, Roberts was instructed to include only a fleeting appearance for Amy and Rory, because his episode would be in production alongside another story -- ultimately The Girl Who Waited -- which would focus on the Doctor's companions. This was necessary to ensure that there was sufficient time to record all thirteen episodes of Season Thirty-Two, as well as the preceding Christmas special.

The Cybermats had not been seen since 1975's Revenge Of The Cybermen

Early drafts of The Lodger had included a villain from Doctor Who's twentieth-century iteration, in the form of the shapeshifting Meglos. Roberts was again eager to incorporate a classic monster in his new script. He felt that the personal nature of the storyline would benefit from a familiar foe, and he was also aware that -- with the exception of some cameo appearances -- Season Thirty-Two otherwise featured only brand-new enemies. Settling on the Cybermen, Roberts decided that they should lurk in the background for much of the episode -- in the manner of Sixties stories like The Moonbase -- so that they would not detract from the interplay between the Doctor and Craig. As such, he also decided to resurrect the Cybermats, the Cybermen's rodent-like servitors which had not been seen since 1975's Revenge Of The Cybermen. Moffat proposed that the new Cybermat should sport fangs, making it more of a physical threat.

Having decided that a key element of the narrative would be the challenges which Craig was facing as a new father, Roberts' storyline acquired the working title “Three Cybermen And A Baby”. This was a reference to the 1987 comedy 3 Men And A Baby starring Tom Selleck and Ted Danson, about three confirmed bachelors who suddenly found themselves caring for an infant. Craig and Sophie's child was originally a girl, first named Grace and later Tess. The disappearances were not a new phenomenon, but occurred every few decades, to be accompanied by strange graffiti. Various electronic and mechanical components were also going missing, and it was this trail which led the Doctor to the store. Its name, Sanderson & Grainger, was partly devised as an homage to an influential teacher from Roberts' youth whose surname was Grainger. Much was made of the Silverleaf Market, which had been held for centuries on the site of the department store; the Cybermat would have been found entombed within its foundation stone. Likewise, a key location within the retail complex was the Silverleaf Spa.

It transpired that the being responsible for the kidnappings was a Cyberscout -- dubbed the Guardian -- which had operated on automatic for centuries, assessing the planet for potential invasion. The graffiti was part of its reconnaissance procedure. Over the years, the Guardian had gradually replaced its defective parts with human limbs and organs when it periodically awoke from dormancy. Nothing remained of the original Cyberman, and it was now protecting Colchester from the other Cybermen, which lay underground in suspended animation. However, when Craig managed to deactivate the Guardian, the other Cybermen were awakened and rampaged through Sanderson & Grainger. The narrative originally ended with Craig destroying the Cybermen with a wrecking ball. This was later revised to hinge on the Doctor transmitting the Guardian's personality into the Cybermen, overwhelming them.

The final two scenes were left for Steven Moffat to write, forming a segue into The Wedding Of River Song

Roberts' first draft was completed in early November. By the end of January 2011, the baby had become a boy named Alfie, and the historical element of the disappearances had been dropped. The episode was now untitled, after a decision to double the number of Cybermen effectively scuppered “Three Cybermen And A Baby”. An element introduced late in the script's development was the Doctor's ability to converse with Alfie; Moffat had come up with the idea of the Doctor speaking “Baby” while writing the season's seventh episode, A Good Man Goes To War, and he now suggested its inclusion to Roberts. The final two scenes -- the three children remembering their encounter with the Doctor, and Madame Kovarian's reunion with River Song -- were left for Moffat to write, forming a segue into the season finale, The Wedding Of River Song.

Block Six of the Doctor Who recording schedule (actually the seventh to go into production) consisted solely of Roberts' episode. It would be directed by Steve Hughes, whose work on Land Girls had caught the eye of executive producer Beth Willis. Since Doctor Who's regular producer, Marcus Wilson, would be overseeing The Girl Who Waited, line producer Denise Paul was promoted to producer for Roberts' adventure. She had previously worked as a script editor on programmes like Rebus and Taggart. When a check was performed on the Cyberman costumes originally created for their twenty-first-century debut in 2006's Rise Of The Cybermen / The Age Of Steel, it was found that many were now in a dilapidated state. Fortunately, this ideally suited Roberts' script, which meant that they would eke out one more appearance before being retired.

Recording for Block Six began on March 3rd at the House of Fraser department store in Cardiff, for scenes in Sanderson & Grainger. Previously branded as a Howell's, the same establishment had posed as Henrik's, the workplace of former companion Rose Tyler, in 2005's Rose. March 4th at the House of Fraser was the only day on which Karen Gillan and Arthur Darvill were needed for filming. More work at the location took place after the weekend, on March 7th and 8th. The new Cybermat prop made its debut on the 7th; unlike the versions seen during the Sixties and Seventies, its appearance was directly patterned after the Cybermen themselves. The same day, BBC Radio One disc jockey Greg James was present for a cameo appearance as a shopper.

From March 9th to 12th, Hughes' team taped scenes set in and around Craig's residence at a house on Church Road in Penarth. Craig and Sophie now lived on the fictional Sheckley Street, in reference to American science-fiction writer Robert Sheckley. On the first day, Matt Smith struck one of the Cybermat props more forcefully than intended, necessitating significant repairs. Sunday the 13th was a day off, after which the final work at Church Road took place on March 14th. By this stage, no fewer than seven babies had portrayed Alfie.

Principal photography on Block Six wrapped up at Doctor Who's regular studio home in Upper Boat. Work there initially spanned March 15th to 17th, with the first two days concentrating on scenes aboard the Cyber ship. On the last day, Hughes turned his attention to material in the tunnel, the lift and the changing rooms, as well as various pick-up shots. On March 20th, the attack on Shona in the changing room area was taped, alongside inserts of the Cybermat. Hughes also shot an ultimately deleted scene in the stock room, in which a warehouse worker was killed by a Cyberman while assembling a mannequin.

Some recording for the Cyberman story still remained to be completed. First, on April 6th, the effects shots of Craig's Cyber-conversion were completed at Upper Boat. Hughes was back on location on the 7th, with Hensol Castle in Hensol providing the setting for Madame Kovarian's confrontation with River Song. The shot of River underwater in the NASA spacesuit was also captured there against a green screen, as were more inserts. Finally, pick-ups of Alfie in Val's arms were taped at Upper Boat on April 21st.

In searching for an episode title, some consideration was given to “The Last Adventure” in order to further build up to the Doctor's putative death in the season finale. On the other hand, Roberts hoped to come up with a satisfactory idea which would incorporate the word “Lodger”. Eventually giving up, he instead generated a list of options which would reflect the department store setting. It was his writing partner, Clayton Hickman, who finally suggested Closing Time.

• Doctor Who Magazine Special Edition #31, 8th August 2012, “Closing Time” by Andrew Pixley, Panini UK Ltd.
• Doctor Who: The Complete History #69, 2018, “Story 223: Closing Time”, edited by John Ainsworth, Hachette Partworks Ltd.