The Doctor escorts Amy and Rory on a date to Venice in 1580. Soon after they arrive, they meet a disconsolate father named Guido whose daughter, Isabella, no longer recognises him. Since enrolling in a school for young women run by the powerful Rosanna Calvierri, she even shuns the sunlight. After witnessing Rosanna's son, Francesco, attack a flower girl, the time travellers become convinced that there are vampires on the loose in Venice. Amy volunteers to enter the House of Calvierri and investigate -- but could the truth be even more sinister?

Although Toby Whithouse had written School Reunion for Doctor Who's twenty-eighth season, it was another project altogether which led to his second script for the programme. Being Human was a supernatural comedy-drama about three flatmates who happened to be a ghost, a vampire and a werewolf. It debuted with a 2008 pilot episode before returning for a full season in 2009; Whithouse was its creator and head writer. Having enjoyed Being Human, new Doctor Who executive producer Steven Moffat asked Whithouse to develop a script for Season Thirty-One. Whithouse had a window of time during 2009 before he was due to start work on Being Human's second season, and he accepted Moffat's invitation.

Whithouse's initial idea involved the Doctor becoming trapped in a kitschy hotel which was really a high-tech labyrinth. However, Moffat and executive producer Piers Wenger became concerned that the concept was too similar to Season Thirty-One's fourth episode, The Time Of Angels, in which much of the action took place in the Maze of the Dead. The hotel narrative was abandoned, although Whithouse would later revive it as Season Thirty-Two's The God Complex.

Rory's involvement would allow the basic premises of Doctor Who to be explored anew through his eyes

Instead, Moffat asked Whithouse to devise an adventure which would reintroduce Amy Pond's fiance, Rory Williams. The character had first appeared in the season premiere, The Eleventh Hour, but he would now join the Doctor and Amy in the TARDIS. Since Rory's involvement would allow the basic premises of Doctor Who to be explored anew through his eyes, the story would act as an ideal mid-season jump-on point for new viewers. Encouraged to think in terms of a romantic escapade, Whithouse suggested vampiric monsters amidst the sumptuous, gothic setting of Venice during the Middle Ages.

The script went by a number of titles during its development, with Whithouse proposing “Blood And Water” and “The House Of Calvierri”. However, given that it was meant to be a gateway into the season for casual viewers, Moffat thought that a more straightforward title would be appropriate. Inspired by the 2006 movie Snakes On A Plane, he proposed “Vampires In Venice”. In June, Mark Gatiss -- who was writing Victory Of The Daleks for Season Thirty-One -- suggested “Vampires Of Venice”, echoing the 1978 Warren Zevon song Werewolves Of London. Whithouse concurred and, by November, the title had undergone only a minor change to The Vampires Of Venice. By this point, the role of the flower vendor in the narrative had been substantially truncated; she was originally called Bianca. Also dropped was Francesco's means of escape after being chased away by Amy and Rory. Whithouse wanted him to climb straight up the wall of a building as a further nod to the vampire mythos, but the effect was deemed too complex and expensive to realise.

As the plans for Season Thirty-One started to gel over the course of 2009, a potential complication was the inclusion of two adventures set in foreign locales. In addition to The Vampires Of Venice, there was also Richard Curtis' Vincent And The Doctor, which took place in Provence, France. Doctor Who could not afford two separate overseas excursions in one year, and the nature of both scripts suggested that the shortcomings of a purely domestic shoot would be apparent on-screen. Furthermore, filming in Venice itself had always been deemed unlikely; the city was regularly awash with tourists, and enormous challenges would have been encountered in trying to dress the modern Venice as its sixteenth-century counterpart.

Instead, the production team decided that a single location would have to be found which could represent both Venice and Provence. They looked to Croatia, parts of which had once been ruled by the Republic of Venice. After considering filming in the coastal city of Dubrovnik, it was decided that the ideal location was the town of Trogir, situated on an island in the Adriatic Sea. Trogir had been under Venetian control for almost four centuries -- including the period in which Whithouse's story was set -- and its architecture still reflected that influence. The Croatian filming would mark the fourth year in a row that Doctor Who had travelled abroad, and the first time that the work had involved two different stories. Indeed, the two-week shoot would represent the longest period of overseas filming ever undertaken for Doctor Who with the exception of the Doctor Who (1996) telefilm, which had been made entirely in Canada.

Line producer Patrick Schweitzer would share some of producer Tracie Simpson's duties

The Vampires Of Venice and Vincent And The Doctor would consequently form Season Thirty-One's fifth recording block, although early plans for the year had positioned it as Block Four. The director would be Jonny Campbell, who was also the boyfriend of executive producer Beth Willis. Given the rigours of the extensive overseas shoot, it was decided that line producer Patrick Schweitzer would temporarily share some of producer Tracie Simpson's duties; he would be credited in both capacities on the two episodes. Before becoming the line producer for Season Thirty-One, Schweitzer had been Doctor Who's production manager for part of Season Twenty-Nine, and had subsequently worked as a line producer on shows like Spooks: Code 9 and Ashes To Ashes.

Filming for The Vampires Of Venice began on November 25th, when Rory's stag night was held at the Bowls Inn in Caerphilly. The same day, material in the TARDIS console room was taped at Doctor Who's usual studio home in Upper Boat. Then, over the weekend of November 28th and 29th, cast and crew flew to Trogir. On the 30th, the city's docks were the venue for the market where the TARDIS materialised. December 1st saw the duel between Rory and Francesco take place at Romeo Square, while Amy pursued the Saturnyne along the adjacent Romeo Street. Sequences around the exterior of the House of Calvierri were recorded on December 4th at the Cathedral of St Lawrence, a thirteenth-century edifice with a distinctive a bell tower constructed over a period of two hundred years from the late fourteenth century.

Following a day off in Trogir on Saturday the 5th, work on December 6th began with street scenes at Petars Place. Campbell's team then moved to the offices of the Mayor of Trogir, which posed as the Calvierri courtyard. On the 7th, more material outside the House of Calvierri was completed at the Cathedral of St Lawrence. This work included Guido punting the Doctor and Rory to the ersatz school, a sequence which was actually filmed entirely on dry land. Cameras were again rolling at Romeo Square on December 8th, for more business in the Venetian streets. The 9th took cast and crew outside Trogir proper, to a jetty on the River Pantan, where Isabella and Rosanna went into the water. To establish that the river was not unreasonably cold, Willis agreed to submerge herself in the chilly mountain-fed stream during the camera tests -- only to find herself fending off a hostile swan which was nesting nearby. The last day in Trogir was December 10th, which began in the alley where Amy and Rory heard the flower vendor's screams. More footage at the House of Calvierri was captured at the Cathedral, and Campbell also completed a number of inserts and effects shots before flying home the next day.

It wasn't until December 16th that Block Five's focus returned to The Vampires Of Venice. Recording through to the 18th took place at St Donat's Castle in Llantwit Major, areas of which dated back to the twelfth century; it was now the premises of Atlantic College, part of the United World Colleges. St Donat's initially served as the exterior of Guido's home on the first day, after which the dining room was dressed as Rosanna's throne room for work which would continue onto the second day. The last day at Llantwit Major saw the bathrooms in the castle's dungeon area serve as the transformation room, plus the corridor. For the Doctor's first encounter with the “Vampire Girls”, the art department prepared a library card which bore a photo of the First Doctor from 1966's The Celestial Toymaker. The listed address was 76 Totter's Lane, which was where the TARDIS was hidden at the start of the very first Doctor Who story, 100,000 BC, in 1963.

Cast and crew then enjoyed the Christmas break, during which viewers witnessed the Tenth Doctor regenerate into his eleventh incarnation at the conclusion of The End Of Time on New Year's Day 2010. Campbell's team resumed work on The Vampires Of Venice on January 7th and 8th at Llancaiach Fawr Manor in Nelson, a sixteenth-century building which offered space suitable as the interior of Guido's home. On the 9th, more Venetian street scenes were recorded at Caerphilly Castle in Caerphilly, along with material in the tunnel beneath the Calvierri estate.

After a day off on Sunday the 10th, the venue on January 11th was Castell Coch in Cardiff, for sequences on the staircase and in the bedroom and basement areas of the House of Calvierri. Finally, various pick-up and effects shots were completed at Upper Boat on the 13th, most notably for the Doctor's ascent of the bell tower. Ironically, the last footage required for the adventure was recorded in Venice itself. On February 13th, visual effects supervisor Dave Houghton travelled there to record plate shots, which would be incorporated into the finished episode.

Throughout Season Thirty-One, Doctor Who's start time had been consistently inconsistent, falling somewhere between 6.20 and 6.30pm. That changed on May 8th, when The Vampires Of Venice was brought forward to 6.00pm to accommodate an extra-length edition of Over The Rainbow, which followed it in the BBC One schedule. This was the earliest timeslot that Doctor Who had occupied since its return to television in 2005.

• Doctor Who Magazine Special Edition #26, 30th December 2010, “The Vampires Of Venice” by Andrew Pixley, Panini Publishing Ltd.
• Doctor Who: The Complete History #64, 2016, “Story 207: The Vampires Of Venice”, edited by Mark Wright, Hachette Partworks Ltd.