A Christmas Carol (TV story)

A Christmas Carol
Doctor:	Eleventh Doctor
Companion(s):	Amy, Rory, Kazran, Abigail
Main enemy:	Kazran Sardick, Elliot Sardick, Sky shark
Main setting:	Sardicktown, Ember, 44th century, Hollywood, California, USA, Earth, mid 20th century
Key crew
Writer:	Steven Moffat
Director:	Toby Haynes
Producer:	Sanne Wohlenberg
Release details
Story number:	213
Premiere broadcast:	25 December 2010
Premiere network:	BBC One
Format:	60 minutes
Production code:	6.X
Confidential:	[[confidential::Principally: Christmas Special 2010 Shorts: Runner, TARDIS, Decorating Bus and Christmas Presents|Principally: Christmas Special 2010 Shorts: Runner, TARDIS, Decorating Bus and Christmas Presents]]
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A Christmas Carol was the 2010 Doctor Who Christmas special. It was the first BBC Wales Christmas special neither written by Russell T Davies nor starring David Tennant.

Furthermore, it broke the record for least delay between UK and US premiere broadcasts of an episode of Doctor Who. Previously held by The End of Time, whose US debut of Part One was a single day later, the delay between BBC One and BBC America (easternmost) broadcasts was a mere eight hours. Australia was equally well-served, with the delay being something on the order of seven hours, depending on time zone.

Behind the scenes, it was significant for the number of new faces in most departments – more than on any other single episode since Rose. Of those new to BBC Wales Doctor Who, the most prominent were those of production designer Michael Pickwoad, costume designer Barbara Kidd, and editor Adam Recht.

Synopsis

Amy and Rory are trapped on a crashing space liner, and the only way the Doctor can rescue them is to save the soul of a lonely old miser. But is Kazran Sardick, the richest man in Sardicktown, beyond redemption? And what is lurking in the fogs of Christmas Eve?

Plot

A spaceship plunges towards an unknown planet. Its captain orders the pilot to try steadying the ship. A distress call has been sent from the ship's honeymoon suite, angering the captain as she does not know who sent it. Amy and Rory, honeymooners aboard the craft, rush to the bridge of the spaceship to see if they can help. Amy was the one who placed the distress call. Rory holds an odd device with a light attached wondering if he has to change the bulb or if the Doctor received the signal; Amy quiets him, praying that the Doctor isn't late. All of a sudden, the ship's computers register a small object approaching the ship; the TARDIS soars into view, beaming the message, "Come along, Pond."

Kazran Sardick introduced

Kazran Sardick, a wealthy, heartless man, owns much of the planet below -- and the cloud belt above, where the ship is trapped. His money comes from a loansharking business he inherited from his father. To secure loans, he cryogenically preserves family members of borrowers for collateral. On Christmas Eve, he meets with one such family in his library. They beg for the release of a family member to spend Christmas Eve with them. Kazran rejects this proposal. He takes a phone call from the president of the planet, asking his permission to land the star-liner safely; he refuses. As he returns to berating the family, a boy notices the sound of the TARDIS landing above them. Suddenly, the Doctor slides down the chimney into the room, calling it a whim. Babbling, he notices a "flashy-lighty thing" machine and tells the group that it's what brought him there; he tries to use the controls to open the cloud belt, but cannot use them. Kazran says the machine is isomorphic. The Doctor wonders who Kazran is, confusing the rich miser as everyone on the planet should know him; the Doctor changes the subject, wondering who the girl in the ice box is. Kazran says she is no one important, amazing the Doctor as he has never met anyone who wasn't important. He asks Kazran to help him save the ship stuck in the cloud belt, but Kazran refuses.

Kazran orders the Doctor and the family removed from his home. The servants grab the Doctor to pull him away. The family's young son throws a chunk of coal at Kazran's head. Kazran moves to strike him, but doesn't; he orders the family and the Doctor thrown out. The Doctor returns to ask why he didn't hit the boy. Though Kazran is less than cooperative, the Doctor quickly pieces together Kazran's personality from the arrangement of his furniture. There is a picture of his father, deceased for twenty years, but Kazran keeps his chair pointed away. Kazran fears being like his father. The Doctor says he is not because he didn't hit the boy.

Outside, the Doctor speaks to Amy over her mobile phone, but is distracted by the sight of some sky fish swimming around a lamp. The unnaturally high water level in the cloud bank, combined with the slight electrical charge, allows the fish to swim amongst the fog. A carol begins playing in the speakers in the street, preventing Amy from hearing the Doctor properly; she informs him that the ship only has an hour left. The Doctor begins panicking about what to do, babbling about what he knows about the situation. Amy asks him what the singing is in the background, but cannot hear him; the Doctor repeatedly tells her that the noise is a Christmas carol, suddenly getting an idea from his repeated sentence. The Doctor suddenly smiles and looks up at Kazran's mansion, saying, "Merry Christmas, Mr Sardick".

Kazran is asleep in his library, dreaming of Christmas Eve when he was only twelve years old and tried to film his encounter with a sky fish. Kazran wakes to find this video being projected onto a wall in his library; in the video, Kazran's father storms into the room and strikes his son, furious that he has disobeyed him by researching the fish. The Doctor appears behind the adult Kazran and wonders if he ever saw the fish; Kazran reveals that this was the day where he first began to realise that there was no one who would ever help him, and that he was on his own in the world. The Doctor reveals that he can change the past and takes off as Kazran derisively declares this to be impossible. The sound of the TARDIS is heard; in the video, young Kazran looks around just as the Doctor steps into his room via the window. He gleefully jumps around, revealing that he is Kazran's new babysitter. The adult Kazran protests that this didn't happen, but suddenly begins to remember that it did.

Young Kazran and the Doctor hide in Kazran's wardrobe, luring the sky fish in through the open window with the sonic screwdriver. Kazran confesses to the Doctor that he is the only student in his class who has never seen a fish; a few minutes later, the Doctor opens the wardrobe door to see a small fish curiously playing with the sonic. The Doctor steps out -- with the adult Kazran, remembering the event, warning him not to -- and deduces how the fish survive in the fog. Suddenly, a large sky shark swoops in and gobbles up the smaller fish and half of the sonic screwdriver. After a struggle, the Doctor manages to stun the shark, which cannot survive outside the fog belt. The Doctor tries to console a young Kazran, confessing there is nothing he can do for the shark without his sonic screwdriver, half of which is still inside the fish; though he has a means of returning it to the sky, it would never survive the trip without some form of life support. To his surprise, Kazran offers an ice box.

Kazran leads the Doctor to a large store room in the basement, which is filled with rows of ice boxes, all of which hold frozen people. Stopping in front of one ice box, Kazran plays its video message: its occupant is a young woman called Abigail Pettigrew, who expresses her gratitude towards Elliot Sardick and her love of the fish. Kazran explains that the people in the boxes are family members of those who have borrowed money from his father, but he insists that they can borrow Abigail's box for the night, unlocking it. Before she fully awakes, the two realise that the shark has followed them to the vault, temporarily revived by swimming in the fog that is settled on the floor. Following a short chase, the shark is put to sleep by Abigail's singing. The Doctor explains that her voice resonates with and aligns the fog crystals in the same way that Sardick's machine does. He places the shark inside the box and brings the trio to the TARDIS, which they use to return the shark to the sky. In the present day, Kazran turns to a picture on the wall, realising that it is of Abigail.

In the TARDIS, the Doctor notices a dial set at eight on Abigail's ice box. When he asks her if it relates to her, she responds by asking if he is one of her doctors; however, he is distracted by something else before she can explain. The Doctor and Kazran return Abigail and her box to the vault, with Kazran promising that they will return and wake her every Christmas Eve from now on; the Doctor feels obliged to do this to keep Kazran happy, and so every time he visits, he takes the pair to new and distant places -- including a sleigh ride through the cloud bank, New York City, and the pyramids. However, with each visit, the dial on Abigail's ice box counts down.

On the sixth Christmas Eve, Abigail finds Kazran much older than before, and appears attracted to him. This Christmas, she requests that they visit her family; she and Kazran watch her sister, brother-in-law, and nephew prepare for the festivities through the window from outside. Abigail cries; when Kazran wonders why, she explains that it is because she is watching the life she will never be able to have. The family invites the trio in for dinner, where Abigail's sister warns her that Kazran will turn out just like his father. Meanwhile, the adult Kazran reflects on his newfound memories.

The following Christmas finds the trio at a 20th century Hollywood party. Kazran finds a crying Abigail by the pool; when he expresses concern for her, she explains that it is time for her to tell him the truth. A few minutes later, the Doctor finds the couple kissing passionately, but impatiently requests to leave, as he has accidentally become engaged to Marilyn Monroe; he leaves with her nevertheless. Abigail sadly tells Kazran that there is nothing that can be done. When the Doctor and Kazran return Abigail to her ice box, the couple bids each other a silent and emotional goodbye. When the Doctor tells Kazran that he'll come back next year, Kazran explains that he has outgrown Christmas and would like to end their yearly ritual. With the Doctor reflecting that Kazran has not changed nearly as much as he would have liked, he offers Kazran his half of the sonic screwdriver in case Kazran ever needs him; Kazran assures him that he won't. Meanwhile, Abigail's dial has returned to one. A few Christmas Eves later, Elliot Sardick is celebrating with his son -- his machine is complete, and the planet is theirs; Elliot finally figured out part of the truth. Confused on what he should do from now on, Kazran runs to his room and takes the screwdriver out of his desk, considering using it to call the Doctor. He turns to see the Doctor standing just outside his window. Kazran goes to the window and looks on as the Doctor gives him a smile, hoping he can be of help. Angrily, Kazran shuts the curtains on him and returns the screwdriver to his desk drawer.

In the present day, Kazran goes to his old and disused room and takes the screwdriver out of the drawer and holds it, contemplating what to do. He receives another call from the president of the planet, who demands the cloud belt be opened and allow the star-liner to land safely. However, Kazran simply refuses; he explains that a very old friend (the Doctor) took many years to show him life isn't fair. Suddenly, a hologram of Amy appears in the library; she is the ghost of Christmas present. She brings him to the vault, where she has summoned dozens of holograms of the spaceship's passengers, who are singing for their lives; she explains that the Doctor was only trying to turn Kazran into a kinder man, but Kazran insists that people can't be rewritten. He destroys the holograms and stops in front of Abigail's ice box, revealing to Amy that Abigail was mortally ill when she volunteered for the ice, and the dial showed how many days she had left to live. If he were to let her out now, he would only have one day with her. Determined, Amy projects a hologram of Kazran onto the ship's deck, where he is able to witness the chaos as the ship plunges towards the planet; the captain angrily tells Kazran that the Doctor has the ship's passengers singing with the hope that they might stabilize the ship -- as Abigail was able to calm the shark -- but it's not working; now, they're doing it because it gives them hope. When he is appealed to again to save the ship, Kazran angrily declares that everyone must die. Amy reveals that the Doctor has been listening, and he returns Kazran's consciousness to his body in the vault, apologising.

The Doctor says that he will now show Kazran the future, and Kazran welcomes this, knowing that he will die alone and afraid as everyone does; he repeats that he doesn't care about the people on the ship and goads the Doctor into showing him the future -- only to be surprised when the Doctor explains that he already is. He points to a twelve-year-old Kazran standing in front of the TARDIS; the boy mistakes his older self for his abusive father, infuriating the elder Kazran, who goes to strike him. However, a rush of memories cause him to break down and embrace his younger self before he decides to save the ship.

Kazran watches in amazement as it snows

With only a few minutes left, the Doctor and Kazran go to the cloud bank controls only to find that Kazran has changed too much and the machine no longer recognises him as Elliot would never let a kind person use the machine. The elder Kazran gives the Doctor his half of the sonic screwdriver; the Doctor realises that he can transmit a signal from one half to the other -- which is still contained in the shark floating in the cloud bank -- but he needs it to transmit something else, something they know will work. Apologising to Kazran, he explains that they will need to release Abigail; her voice resonates perfectly with the fog crystals, and only that will calm the sky. Kazran is reluctant to let her out, but when he does so, she insists that she would have chosen Christmas Day with him for her final day. She begins to sing her song, which unlocks the cloud belt and causes a snowfall for the first time in years. The ship's crew realises that they are able to land the ship safely, and Rory and Amy embrace. The Doctor departs with young Kazran as old Kazran and Abigail wave goodbye; they then notice that a sleigh lies behind where the TARDIS was.

Amy and Rory meet up with the Doctor on the ground, where she notices he has built numerous snowmen along the street. The Doctor wonders why they are dressed in their costumes; Rory explains that they lost their luggage despite having a safe landing. However, the Doctor wonders why they are dressed like that at all; Amy hushes the Doctor and tries warming herself up. Rory asks if the Doctor has any more ideas for honeymoon locations. The Doctor begins babbling on about a carnivorous "moon" made of "honey" that has some "lovely views"; Rory is less than excited to hear about this idea and walks into the TARDIS. Amy asks the Doctor if it is okay to leave things the way they are; Abigail and Kazran only have one day left together. However, the Doctor tells her that if nothing ever ended, nothing would ever get started. Rory pops out of the TARDIS, saying he answered the phone; Marilyn has called the Doctor. The Doctor tells Rory to inform Marilyn hat he will call her back, "and that was never a real chapel".

Amy wonders where Kazran and Abigail have gone, but the Doctor only answers "Christmas"; Amy enters the TARDIS and the Doctor follows shortly after looking up into the sky. The scene pans above to show the snowing night sky as Kazran and Abigail fly by on their shark-drawn sleigh.

Cast

• The Doctor - Matt Smith
• Amy Pond - Karen Gillan
• Rory Williams - Arthur Darvill
• Kazran Sardick / Elliot Sardick - Michael Gambon
• Abigail Pettigrew - Katherine Jenkins
• The Captain - Pooky Quesnel
• Middle Kazran - Danny Horn
• Young Kazran - Laurence Belcher
• Co-Pilot - Micah Balfour
• Eric - Nick Malinowski
• Older Benjamin - Steve North
• Chief Servant - Tim Plester
• Isabella - Laura Rogers
• Pilot - Leo Bill
• Boy - Bailey Pepper
• Benjamin - Bailey Pepper
• Old Isabella - Meg Wynn-Owen

Crew

Executive Producers   Piers Wenger, Beth Willis and Steven Moffat

General production staff Production Executive - Julie Scott Line Producer - Diana Barton Location Manager - Iwan Roberts Unit Manager - Rhys Griffiths Production Co-ordinator - Claire Hildred Assistant Production Co-ordinator - Helen Blyth Production Assistant - Charlie Coombes Production Secretary - Scott Handcock Production Accountant - Dyfed Thomas A/Production Accountant - Rhys Evans Script department Script Executive - Lindsey Alford Camera and lighting department 1st Assistant Director - Mick Pantaleo 2nd Assistant Director - James DeHaviland 3rd Assistant Director - Heddi-Joy Taylor-Welch Assistant Directors - Janine H. Jones, Michael Curtis Script Supervisor - Phillip Trow Camera Operator - Robert Arrowsmith Focus Pullers - Steve Rees, Simon Walton Grip - Gary Norman Camera Assistants - Simon Ridge, Svetlana Miko Boom Operator - Laura Coates Gaffer - Mark Hutchings Best Boy - Pete Chester Electricians - Ben Griffiths, Gareth Sheldon, Bob Milton, Peter Scott	Art department Art Director - Stephen Nicholas Production Buyer - Ben Morris Petty Cash Buyer - Kate Wilson Set Decorator - Julian Luxton Storyboard Artist - Rod Knipping Concept Artist - Richard Shaun Williams Graphic Artist - Christina Tom Standby Props - Silas Williams, Katherine Archer Standby Carpenter - Justin Williams Standby Art Director - Ciaran Thompson Standby Rigger - Bryan Griffiths Standby Painter - Helen Atherton Store Person - Jayne Davies Props Master - Paul Aitken Props Chargehand - Rhys Jones Dressing Props - Stuart Mackay, Kristian Wilsher Props Driver - Medard Mankos Props Makers - Penny Howarth, Nicholas Robato Construction Manager - Matthew Hywel-Davies Construction Chargehand - Scott Fisher Practical Electrician - Albert James Graphics - BBC Wales Graphics Costume department Costume Supervisor - Bobbie Peach Assistant Costume Designer - Samantha Keeble Costume Assistants - Jason Gill, Yasemin Kascioglu	Make-up and prosthetics Make-up Supervisor - Pam Mullins Make-up Artists - Allison Sing, Vivienne Simpson Prosthetics - Millennium FX Movement Stunt Co-ordinator - Crispin Layfield Stunt Performer - Gordon Seed Casting Casting Associate - Alice Purser General post-production staff Post-production Supervisor - Nerys Davies Post-production Co-ordinator - Marie Brown Assistant Editor - Becky Trotman On-line Conform - Mark Bright Special and visual effects Visual FX Producer - Beewan Athwal VFX Editor - Cat Gregory Senior Visual Effects Artist - Craig Higgins Colourist - Mick Vincent Model Maker - Julia Jones Sound Sound Recordist - Bryn Thomas Dubbing Mixer - Tim Ricketts Sound Maintenance Engineer - Dafydd Parry Sound Supervisor - Paul McFadden Sound Effects Editor - Paul Jefferies Sound Editor - Doug Sinclair Foley Editor - Jamie Talbutt

Not every person who worked on this adventure was credited. The absence of a credit for a position doesn't necessarily mean the job wasn't required. The information above is based solely on observations of the actual end credits of the episodes as broadcast, and does not relay information from IMDB or other sources.
This episode marked the Doctor Who debut of production designer, Michael Pickwoad, the BBC Wales debut of costume designer, Barbara Kidd, and the first time that something like 20 team members had been credited for their work on Doctor Who. It was the biggest sea change of behind-the-scenes personnel in BBC Wales history, much bigger, in fact, than the changes that had occurred with The Eleventh Hour.  In CON: Charlie McDonnell - Runner, Janine H. Jones was described as a runner, and even depicted as delivering tea to cast and crew. However, she's credited here as an "assistant director", albeit lower than the 3rd AD, which does still essentially mean that she was a runner.  This is the first episode of the BBC Wales series in which the title "Script Editor" is not used.

References

Culture

• Abigail's song mentions "Silence" several times.
• The Doctor wonders if Kazran has seen Mary Poppins.

The Doctor

• The Doctor gets married to Marilyn Monroe - although questioning the validity of the chapel - and she has the number to the TARDIS phone.
• The Doctor displays an inability to perform a card trick. (TV: Rose)
• The Doctor has employees leave by having them mysteriously win the lottery as in School Reunion.

Locations

• The Doctor, Kazran and Abigail appear to have visited (according to Kazran's photos): the Pyramids and the Sphinx in Egypt; the Sydney Opera House and Uluru in Australia; the Eiffel Tower in France; and the Statue of Liberty, the Empire State Building, and 1952 California (specifically Hollywood) in the United States of America.

Species

• The Eleventh Doctor mentions face spiders.

Story notes

• A Christmas Carol is loosely based on the Charles Dickens novel of the same name, with Kazran Sardick being Ebenezer Scrooge, the Doctor being the Ghost of Christmas Past, Amy being the Ghost of Christmas Present and Kazran himself being the Ghost of Christmas Yet to Come.
• The first footage from this special was screened on 19 November in the form of a trailer as part of the BBC's Children in Need.
• The interior design and look of the crashing space liner is very similar to the style of the Starfleet ships from the 2009 Star Trek film, in terms of layout (though more compact) and touchscreen controls. There is also moderate use of lens flares during the scenes on the ship, which was significantly used during the interior shots of the various ships in that film. The space liner is described as "galaxy class", which is the class of the USS Enterprise in Star Trek: The Next Generation. In addition, one of the crewmen is of African descent and wears an odd eyepiece, similar to the character of Geordi LaForge.
• This is the first story to feature Arthur Darvill's name in the opening titles.
• Steven Moffat said before it aired that this episode would be the most "Christmassy Christmas special ever," adding, "It's all your favourite Christmas movies at once, in an hour, with monsters and the Doctor and a honeymoon..."
• This is the first Christmas special since The Christmas Invasion to feature the Doctor's regular companions. This is also the first Christmas special not to be set primarily on or near Earth.
• Paul Cornell's short story "The Hopes and Fears of All the Years" likewise features the Doctor visiting an individual every year at Christmas time (though in that case on Christmas Day, not Christmas Eve) by virtue of time travel. Both stories also involve the Doctor arriving on the scene by coming down the chimney.
• This is the first Christmas special not to feature David Tennant and the first one not to be written by Russell T Davies. It is the first one to feature Matt Smith and first to be written by Steven Moffat.
• The shark, despite being a female, was named "Clive" behind the scenes. Smith and Belcher also claimed to have called it "Percy" and "Clyde".
• Murray Gold revives his custom of composing a special song for the Christmas Specials, after not doing so for TV: The Next Doctor or The End of Time.
• Excluding the little fish and Abigail Pettigrew and Elliot Sardick's off-screen deaths, this is the first Christmas special without a character's death.
• Since Amy was replaced with a Ganger in the following season, this is presumably the last episode to feature the actual Amy Pond until the end of The Almost People.
• "Abigail's Song" is the first English-language song to be composed for Doctor Who since "The Stowaway" and is the first original song to actually play a direct role in resolving the plot.
• Michael Gambon is well known for taking over the role of Albus Dumbledore in Harry Potter and the Prisoner of Azkaban, coincidentally the only Harry Potter film that includes time travel.
• The Doctor travelling back in time to make someone react more favorably to him was part of the plot of the Decalog 3: Consequences short story Continuity Errors, also written by Moffatt.

Ratings

• 10.3 million (Overnight)
• 12.11 million (BARB)

Rumours

• The villain has been confirmed by the BBC to be a CGI "Flying Shark". Although the main enemy was Kazran Sardick, there was a menacing, flying shark.
• The episode could be a musical. This was false, although Katherine Jenkins did sing.
• The episode will be set on a planet that looks Victorian and will have flying sharks.This was true.
• In the episode, the Eleventh Doctor will get engaged. He was accidentally engaged to Marilyn Monroe, and this leads up to a gag at the end of the episode.
• The Doctor will pose as a Ghost of Christmas Past. In a trailer for the BBC's Christmas season, the Doctor is heard saying "I'm a ghost of Christmas Past".This was true, with the Doctor travelling back in time to Kazran's past, and from there, affect his future.

Filming locations

to be added

Production errors

If you'd like to talk about narrative problems with this story — like plot holes and things that seem to contradict other stories — please go to this episode's discontinuity discussion.

• When the Doctor first goes back to Kazran's childhood, the light from the TARDIS windows can be seen through the crack in the door after the supposed departure.
• According to a previous episode in which Rose and Doctor travel to the past to see Rose's father, touching one's past self causes a paradox. In this episode, however, Kazran is seen touching his past self and no such thing can be observed.

Continuity

• Amy says, "Don't be late, Doctor, just this once." (TV: The Eleventh Hour)
• The Doctor sends a message to Amy saying, "Come Along Pond." (TV: The Big Bang)
• The Doctor attempts and fails to perform card tricks. He previously displayed this in TV: Robot and TV: Rose.
• The Doctor produces a photograph of himself and Father Christmas with Albert Einstein at Frank Sinatra's hunting lodge. It was previously suggested in TV: Time and the Rani that the Doctor and Einstein were friends.
• While in the honeymoon suite, Amy wears her policewoman kissogramme garb, (TV: The Eleventh Hour) and Rory wears a Roman Centurion's outfit, just like the one worn by his Auton self, and previously by his real self (as seen in a photograph in Amy's house), or this was the Christmas event that the photograph was of. (TV: The Pandorica Opens)
• The Doctor is seen, once again, in a fez, but this time it's because he's actually going to Egypt. Kazran's photographs prove that the time travellers spent one Christmas Eve at the pyramids.
• During one of his visits to Abigail, the Doctor wears a scarf similar to the one worn by his fourth incarnation.
• The Doctor has previously observed and attempted to use devices with isomorphic controls to no avail, a notable example being the Master's laser screwdriver. (TV: Last of the Time Lords) The Doctor has also previously stated (apparently falsely) that the TARDIS has isomorphic controls. (TV: Pyramids of Mars)
• Abigail says she cannot enter her home, before seconds later seeing the Doctor within - closely resembling the Doctor telling Amy not to interfere before she sees him on the TARDIS monitor doing so. (TV: The Beast Below)
• The Captain claims that "Christmas is cancelled!" (TV: The End of Time)
• The Doctor once again says, "Geronimo!" (TV: The End of Time, The Beast Below, The Big Bang)
• The Doctor gets himself into a problematic marital situation with Marilyn Monroe. He previously had a failed marriage with Queen Elizabeth I, and he has stated that he is "rubbish at weddings... especially my own." (TV: The Shakespeare Code, The End of Time, Blink')
• The Doctor, when speaking to Kazran, said, "900 years of time and space, I've never met someone who wasn't important". He said something along the same lines to Craig Owens when Craig was sick. (TV: The Lodger)
• The Doctor previously mentioned having seen fish that fly. (TV: Marco Polo)
• If Melody Pond was conceived on Amy and Rory's wedding night (TV: The Big Bang) as suggested in TV: A Good Man Goes to War then Amy is pregnant with River in this episode.
• The Doctor gives Sardick a choice: help those people on the starliner or face the consequences. When he refuses the Doctor says, "Whatever happens here tonight, remember: You brought this on yourself." The Tenth Doctor told the Empress of the Racnoss much the same thing when he offered her a choice to either leave or face the consequences. (TV: The Runaway Bride)
• This is not the first time the psychic paper failed. (TV: Army of Ghosts, The Shakespeare Code)
• The Byzantium was also identified as a Galaxy Class ship. (TV: The Time of Angels)

DVD release

This story was released on DVD and Blu-ray on 24 January 2011 in UK markets and 15 February 2011 in North American markets.

Footnotes