The Unicorn and the Wasp

The Unicorn and the Wasp was the seventh episode of the fourth series of Doctor Who. It saw Doctor Who's take on the disappearance of famous author Agatha Christie in 1926, giving a possible, yet unlikely, answer as to why she vanished.

The episode first aired on 17 May 2008.

Synopsis
In 1926, Agatha Christie mysteriously disappears, only to be found ten days later at a Harrogate hotel, The Harrogate Hydro, with no memory of what happened to her. What could have been the cause? Was it a nervous breakdown? Was it a cry for help? Or was a giant alien wasp and a mysterious stranger known as the Doctor involved?

Plot
The TARDIS materialises outside a country estate, hidden by trees; the Doctor and Donna Noble depart. The Doctor smells the air and tells Donna that they have landed in the 1920s. Donna wonders if the Doctor really could tell the year by smell, but then points out that the vintage car coming up the driveway may have given it away; they both hide.

The car's driver, Professor Peach, parks and is greeted by his old friend, the butler Greeves, just as the local reverend, Arnold Golightly, arrives on his bicycle. As the servants take their luggage, they exchange a few words, and Peach decides to go to the library to do some research on his own. Golightly tells Professor Peach that constantly working will be the death of him; they're at a party, he should try to relax.

Watching from the side of the house, Donna tells the Doctor to forget about planet Zog as a party in the 1920s is much more fun. The Doctor points out that they're not invited, but then pulls out his psychic paper, saying, "Oh, I forgot. Yes we are". They head back to the TARDIS so Donna can find a dress from the 1920s to wear.

In the library, Professor Peach discovers a secret amongst the papers. Suddenly, a shadowy person comes in, and Peach quickly hides his papers, telling the person that he was just doing some mundane research. He then asks the mysterious person what he is doing with a lead pipe. The mysterious person's eyesight becomes purple as Peach mumbles, "That's impossible!". The mysterious person, revealed to be a giant wasp, bludgeons the professor to death.

Back outside, the Doctor is waiting outside the TARDIS for Donna to finish changing, reminding her that they'll be late for cocktails. Donna comes out in a dress and the Doctor says she looks lovely. They head for the front lawn, and after a greeting by Lady Eddison, who wonders who they are, the Doctor uses the psychic paper to fake an invite and comes up with a story about meeting her at an ambassador's reception. Lady Eddison excuses herself as she is being precautious because the Unicorn is about. The Doctor, at first, mistakes this for an actual unicorn before Lady Eddison clears up the confusion by explaining the Unicorn is a jewel thief who is on the loose and has just struck again.

They then meet Lady Eddison's wheelchair-handicapped husband, Colonel Hugh Curbishley, and their son Roger. Donna is confused why Lady Eddison has a different surname and the Doctor explains that the Eddison title descends through Lady Eddison; one day Roger will be Lord Eddison. Roger secretly flirts with Davenport, the male servant; Donna and the Doctor easily pick up on the homosexual relationship between them and whisper quips to each other. Next to arrive is Reverend Golightly, who Lady Eddison congratulates on the apprehension of two boys who tried robbing the church last Thursday. Following him is fashion model Robina Redmond. Last to come is British mystery writer, Agatha Christie, whom the Doctor is ecstatic about meeting as she is another of his favourite authors. Still a young writer, she has recently published her sixth novel; the Doctor and Donna are both impressed. Seeing that they are a person short, Lady Eddison tells Miss Chandrakala to go into the house and find Professor Peach; Golightly mentions that Peach said he was going to the library.

The Doctor acquires a newspaper from Hugh's chair and reads it. He then shows Donna the date - 8 December 1926, the day Agatha Christie disappeared. He explains that Agatha had just discovered that her husband is having an affair. Being British, these people would normally just carry on, but this time, that didn't happen. Tomorrow morning, her car will be found abandoned by the side of a lake. In ten days, Agatha will turn up in a hotel in Harrogate with no memory of what happened. A surprised Donna then asks the Doctor, "Then it's about to happen..."; he finishes "...right here, right now." Their train of thought is interrupted when Ms Chandrakala comes running back, yelling that the professor had been murdered in the library.

The Doctor and Donna race to the library, followed by Agatha. The Doctor determines that blunt force trauma was the likely cause of death, and notes that the watch broke as the victim fell - pinpointing the exact time of death to 4:15 PM. Agatha discreetly takes a piece of paper from the fireplace, but the Doctor notices her reflection in the bookcase. Donna softly asks the Doctor if he noticed the professor's murder is like the board game Clue. Everyone else comes in and decides to call the police. However, the Doctor uses his psychic paper to identify himself as a Scotland Yard, having Agaha keep them in the sitting room until he's ready to question them. Donna asks the Doctor why they aren't calling the police as he discovers "morphic residue" - a by-product of shapeshifting - on the floor; one of the guests isn't human. She then says the situation is weird; Agatha Christie wasn't litteraly surrounded by murder, comparing it to "Charles Dickens, surrounded by ghosts at Christmas." The Doctor hints he experienced this as Donna then asks if they could find Noddy. Thinking for a moment, Donna asks the Doctor if Noddy is real; the Doctor confirms he isn't before rushing off.

While the Doctor tastes the residue to determine what left it, they walk past the sitting room. Donna then asks if it's like Murder on the Orient Express, where everyone did it. Agatha overhears this and finds the idea brilliant. Donna tries to tell her it's one of her best books, but the Doctor tells her "not yet", hinting to keep quiet. The Doctor explains he and Agatha will question the suspect, handing Donna a magnifying glass to search the rooms upstairs for more residue. The Doctor expresses joy at being able to solve a murder mystery with Agatha. She reluctantly agrees, unhappy at the Doctor's casual attitude toward the murder.

During the interviews, while the guests recount their stories of what they were doing at 4:15 PM, flashbacks reveal that each is hiding something, except for Reverend Golightly (who claims to have been unpacking in his room). Lady Eddison claims to having been taking tea, though she was surreptitiously consuming liquor AKA "liquid courage". Robina Redmond claims to have been using the toilet, but was in the bathroom loading a tiny pistol. Roger Curbishley, Lady Eddison's son, claims to have been walking alone, when he was attending a tryst with his lover Davenport, one of the servants. Colonel Hugh claims he was reading military memoirs in the study, though he was viewing erotica while fantasising about can-can dancers, which causes him to slip into a second flashback. The Doctor manages to snap him out of it, much to Hugh's embarrassment.

Agatha points out that they have nothing to go on, mentioning they need to use "the little grey cells". The Doctor goes on about how he likes Poirot and begins remembering about how he had been to Belgium, where an insane computer had kidnapped Charlemagne. Agatha snaps him out of this flashback and he apologises. She then points out Charlemagne lived centuries ago. The Doctor tells her that he has a very good memory before being told he missed an important clue. The Doctor then sarcastically asks if it's the bit of paper she nicked from the fireplace, explaining how he saw her. Agatha is surprised by the Doctor noticing her, calling him a "crafty man", much to his amusement. Agatha produces the paper she removed earlier with the letters "a-i-d-e-n", preceded by one illegible letter: it obviously spells the word "Maiden", although neither she nor the Doctor is able to divine its significance. They hope Donna will be able to bring them more clues.

Meanwhile, Donna comes upon a locked door during her part of the investigation and encounters Greeves, who informs her that Lady Eddison has commanded the room be shut for the last 40 years after recovering from malaria in it. On Donna mentioning being an investigator from Scotland Yard, Greeves has no choice but to open the door for her; she dismisses him. Inside the room, it is bare except for a few children's toys, making Donna wonder even more why it has been sealed. She then hears a buzzing from the window, commenting that the 1920s still have bees.

When she pulls back the curtain, she instead finds a giant wasp outside the window and begins yelling for the Doctor. The wasp breaks in and tries attacking her as Donna backs up to the window. Using the magnifying glass, Donna burns the wasp with the sun's rays, allowing her to run outside just as the wasp impales its stinger in the door. The Doctor and Agatha arrive, asking what she was yelling for. Donna tells the Doctor that she encountered a giant wasp, piquing the Doctor's curiosity while Agatha dismisses the idea, thinking she was scared away by a normal, tiny insect. Donna defends herself: "When I say 'big', I don't mean tiny; I mean flipping enormous!" and points to the stinger still embedded in the door.

The Doctor is amazed/shocked and tells Donna to let him have a look, and opens the door to find that the wasp has "buzzed off". Agatha tries to touch the stinger, but the Doctor tells her not to as he takes out a vial and pencil to collect a sample, saying that there are plenty of alien insects, but none should be in this galactic vector. Agatha understands some of the Doctor's words, but now thinks he's insane. Donna asks the Doctor if the wasp was harmless now that its stinger is gone; it's not. The Doctor tells her that because of its size, the wasp will be able to grow a new one. Agatha then tells him that there is no such thing as giant wasps. The Doctor tells her that she is right, but points out that the question is whyit's here. In the kitchen Davenport is speculating about the murder with another of the servants while cooking dinner, wondering about who would want to kill Professor Peach. The other servent sepcualtes that it's what happens when a party is thown by the rich and famous. Miss Chandrakala, als there, dismiess the idea, telling them to get back to work. However, she then has an epithany, realising exactly what Professor Peach had discovered in the libraray when he was murdered. Miss Chandkala tells them that she must speak to Lady Eddison and rushes off outside to find her. However, an unseen figure, possibly the wasp, watches from above and knocks over a gargoyle from the ledge; it lands on Miss Chandrakala with a loud thud.

Hearing the scream of Miss Chandrakala, the Doctor, Agatha, and Donna rush outside to find her slipping away. Passing on, Miss Chandrkala leaves them with a cryptic message, "The poor little child..." Seeing the wasp hovering above the building, the Doctor, Donna and Agatha give chase with Donna commenting on how the roles are reversed this time. Agatha is still in denial about the wasp being real, thinking it's some kind of illusion. They find it coming in through a skylight and the Doctor tries reasoning with it before they barely dodge an attack. Donna gets the wasp's attention and holds up the magnifying glass to threaten it. It flies into the next hall as the Doctor yells for everyone to hurry and not let it return to human form. When the Doctor shouts, "Show yourself," all of the doors open and every suspect appears; "That's just cheating".

Everyone gathers in the sitting room, where they pressure Agatha to solve the murder(s). However, she tells them that she is only a writer and that the Doctor is their best chance at solving the case now. She retreats to the garden. Donna goes out with her and compares her similar trouble with men along with foreknowledge that someday her books may be turned into films. Agatha, however, thinks that her books may fade out of interest and she will be forgotten. She then notices a box that has crushed some flowers.

They take the box to the Doctor, who is in the sitting room; the contents are full of a thief's tools, possibly the Unicorn. Greeves arrives and gives them their drinks as Donna asks the Doctor what he found out about the venom from the stinger. Taking out the vial, the Doctor explains that the venom comes from a Vespiform, a race of aliens who have hives in the Silfrax Galaxy. However, the question remains as to why it's here and acting like a character out of one of Agatha's books. Donna then asks Agatha what Miss Marple would do, pointing out the character's M.O. and again noticing that she has given yet another idea to Agatha; Donna decides to have Agatha copyright Miss Marple to her. The Doctor then calls to Donna with a blank face, saying something is inhibiting his enzymes. Suddenly, the Doctor starts to have convulsions, realising someone has poisoned his drink as Agatha deduces the poison is cyanide.

The Doctor rushes to the kitchen, asking for ginger beer. Upon finding a bottle, he drinks some and then pours the rest on himself. Agatha tells him that as an expert in poisons, she knows cyanide is fatal. The Doctor points out that he (being a Time Lord and not a human) can stimulate the inhibited enzymes into reversal, curing himself. He then asks for protein (in walnuts), salt (contained in anchovies; pure salt is apparently "too salty"). He then asks for a big shock, whih Donna complies with by kissing him; being just friends, as he wanted, the Doctor is shocked by this. The Doctor then exhales the poison in a cloud of smoke, saying he should "de-tox" more often. Agatha calls the Doctor impossible and then asks who he really is.

At dinner that night, the Doctor points out that they are still having dinner even thought two people have died. Lady Eddison asks what he would want them to do; they are British, they carry on. The Doctor then tells the guests that one of them has failed to poison him and that anyone of them could have put cyanide in his drink before mentioning it gave him an idea. Golightly asks what it is and the Doctor responds, "Poison, drink up" as the diners are eating soup. Donna chokes on her soup for a moment before the Doctor tells everyone that the soup has been laced with pepper. Colonel Hugh finds the extra spice delightful before the Doctor explains that the active ingredient in pepper is pepperine, normally used as an insecticide, asking if anyone has "the shivers".

A buzzing is heard. Lady Eddison exclaims, "It can't be!" The lights are blown out when a sudden gust of wind blos open the windows and everyone spreads out, against the Doctor's orders and to his own growing annoyance. Agatha demands that the "demon" show itself, which it does, above a painting. The Doctor and Greeves pull Donna and Agatha out of the dining room; the Doctor tells Agatha that he'll cover her because she has got a long life o live yet. As the Doctor takes a sword from a coat of arms, Donna jokes, "At least we know the butler didn't do it". The Doctor opens the door, asking, "Who did?" The lights come back on and the wasp is nowhere to be found. Lady Eddison then notices her necklace, 'the Firestone', is stolen. Davenport then sadly says Roger's name. Robina looks over to Roger and screams in horror; the Vespifrom has stabbed Roger in the back. Lady Eddison goes over to her son, crying over his death.

Later, in the sitting room, Agatha is trying her best to cope with what's happened with the Doctor at her side. Donna enters, feeling sorry for Davenport as he can't mourn Roger. Agatha then asks Donna if she inquired about the Firestone; it is a priceless jewel that Lady Eddison brought back from India 40 years ago. The Doctor then begins wondering about the Vespiform; "It can sting; it can fly. So, why's it playing this game?" Agatha tells the Doctor to stop as she knows the murderer is as human as them. The Doctor then realises that Agatha is right; he's been so caught up in figuring out this giant wasp, that he's forgotten that she's brilliant. Agatha just says that she doesn't believe her work is any good before the Doctor points out that the reason her books are so good is because she knows the human mind well; she knows what tiny little things can lead to murder, saying that "if anyone can solve this case, it's you".

With her confidence restored, Agatha, the Doctor and Donna call the remaining four suspects together in the sitting room. The Doctor introduces Agatha and lets her begin. She starts with Robina Redman, who she quickly exposes as an imposter due to her terminology and the fact they found the thief tool box below her bathroom window. Agatha points out Robina must have thrown them out when she heard Donna was searching the rooms; "Robina" is the Unicorn. Losing her fake accent, the Unicorn reveals she still has the Firestone and hands it over to the Doctor; she is not the murderer. Agatha then turns her attention to the Colonel, who is now revealed to not need a wheelchair; he only pretended in order to keep Lady Eddison at his side as he feared she would fall in love with another man. When asked how she figured out the truth, Agatha tells the Colonel that she didn't and she was going to say he was innocent.

Agatha picks up the Firestone and asks Lady Eddison to explain how she brought it back from India, then suffered from malaria and kept herself confined in her room. Agatha concludes that Lady Eddison came back from India pregnant and concealed it with the aid of Miss Chandrakala. The Doctor then says, "It was no ordinary pregnancy", prompting a confused Lady Eddison to wonder how he knew. Taking control from Agatha as they are in his territory, the Doctor asks Lady Eddison why she said, "It can't be" back in the dining room. Though Lady Eddison tells the Doctor that he would never believe her, Agatha tells Lady Eddison that he has opened her mind to believe many things.

Lady Eddison explains: it was 1886, India; she was alone one night when she saw a purple shooting star land nearby. The next day, she met a young man named Christopher, whom she quickly fell in love with and had an affair. Christopher revealed he was a Vespiform who took human form to study Earth; Lady Eddison loved him so much, she didn't care. However, he died soon after, during a monsoon, but he left her the Firestone. Out of shame of the scandal her out-of-wedlock baby could bring, Lady Eddison sadly gave him up for adoption. Donna then realised that "maiden" on the paper meant "Maiden name", which Agatha verifies as the reason Professor Peach was killed; he found out who the child was and who his parents were. Agatha notes that Lady Eddison is innocent of murder and turns it back over to the Doctor.

The Doctor points at Donna, saying that she was right, everything is being acted out like a murder mystery, which causes him to next point at Agatha, explaining that she wrote those clever books. Donna then wonders if Agatha was involved, but the Doctor dismisses the idea, telling her that Lady Eddison is her biggest fan. The Doctor then asks what she was doing the previous Thursday and learns that Lady Eddison was reading her favourite Agatha Christie book (The Murder of "Roger" Ackroyd) before being asked how it is relevant. The Doctor then points out that the failed robbery that Golightly foiled at the church also happened on Thursday.

It would be impossible for Golightly to defeat two strong men, and it has been forty years since Lady Eddison gave birth… and Golightly is celebrating his 40th birthday. Also, Golightly said earlier that he was taught by the Christian fathers, meaning that he was raised in an orphanage. The Doctor notes that Golightly got angry (a proper deep anger) for the first time in his life, and he transformed for the first time in his life, which allowed him to frighten the thieves into submission. His alien biology was awakened. Also, the Firestone is not a jewel at all, but a Vespiform telepathic recorder, part of Golightly's very essence. When Golightly activated, the Firestone beamed his identity directly into his brain. He also accidentally received the works of Agatha Christie as his template for how the world should work because Lady Eddison was thinking about the plots: hence the style of the murders.

Donna then wonders if Golightly is the murderer and the Doctor answers, "Yes". Slightly miffed, Golightly says the evening has been entertaining and asks Lady Eddison if she believes what she's heard, buzzing on her name. The Doctor asks what he said and Golightly buzzes "Lady Eddison" again before the Doctor tells him he's buzzing. Golightly warns the Doctor not to make him angry before the Doctor asks why. Walking away from everyone, Golightly sneers at them, saying that humans worship tribal "sky gods" while he is so much more. After the upload of information, he wanted to take what was his (inheriting the Eddison title).

Becoming blinded by rage, Golightly focuses on Agatha Christie, asking why he shouldn't just kill her, as pink light surrounds him. Completely losing his temper, Golightly transforms into his wasp form, prepared to kill everyone. Agatha snatches the Firestone, screaming that her mind--that which had taught the Vespiform to kill--will find a way to destroy him. Golightly pursues her, as her thought patterns are linked to him through the Firestone. She takes a car and drives away, hysterically repeating, "It's all my fault." The Doctor and Donna follow her in the late Professor Peach's car, with the Doctor ominously warning that "time is in flux" - that there is no guarantee that Agatha will survive, which could leave history severely damaged.

Agatha leads the creature to a lake, where she is "the honey in the trap", calling Golightly to her. The Doctor and Donna arrive and he notes that Agatha is linked to his mind. She plans to kill herself in order to kill Golightly. The Doctor tries to persuade Golightly that he was not meant to kill, but he does not listen. Donna seizes the opportunity to snatch the Firestone and hurl it into the water. Golightly pursues it and drowns, as his father had, in the Indian monsoons forty years before. "How do you kill a wasp? Drown him, like his father", Donna says coldly. The Doctor then points out that Golightly couldn't control himself.

Agatha gives a poetic speech as the purple light fades in the water. The Doctor decides to call this adventure "Murder at the Vicar's Rage"; Donna gives him a look. He then says the title needs some work. Agatha tells the Doctor there is just one more mystery left; who is he? However, she then collapses in pain; the Doctor catches her. The Doctor realises that the two are still linked and if it dies, so does Agatha. However, Golightly cuts the link right before passing, which causes Agatha to pass out, much to the Doctor's surprise; "Right at the end, the Vespiform choose to save someone's life". Donna then wonders what will happen now as the Doctor finally figures out how Agatha lost her memory; it was caused by the psychic trauma. Keeping with the established timeline, the Doctor takes Agatha in the TARDIS and deposits her at the Harrogate Hotel ten days later.

Donna wonders about Lady Eddison, the Colonel and the servants, asking if they would tell anyone about what happened. The Doctor reminds her that they are too British to tell such a shameful story and that the Unicorn escaped and managed to get back to London. Donna then wonders what will become of Agatha. The Doctor explains that she will get married again and continue writing her books. Donna tells the Doctor that Agatha never thought her work was any good as they board the TARDIS.

In the TARDIS, the Doctor tells Donna that he thinks Agatha never quite forgot what happened as he pulls open a hatch below the TARDIS floor and pulls out a chest. Amongst the various knick-knacks he tosses out of it, the Doctor produces Death in the Clouds, a novel which features a gigantic wasp on the cover. Donna is shocked as the Doctor points out that she had such a great mind, some of the details bled through, stuff her imagination could use, such as Miss Marple; Donna remarks she should have had Agatha sign a contract. However, the Doctor then has Donna look at the copyright page in front, which shows that the book is from the year five billion; Agatha Christie is quite literally the most popular writer of all time.

Donna then reminds the Doctor that Agatha never thought her work was good. The Doctor tells her nobody knows how they're going to be remembered, something that keeps him travelling. He asks Donna if they should continue onwards and she agrees as he pulls a lever on the console.

Cast

 * The Doctor - David Tennant
 * Donna Noble - Catherine Tate
 * Agatha Christie - Fenella Woolgar
 * Lady Clemency Eddison - Felicity Kendal
 * Reverend Golightly - Tom Goodman-Hill
 * Colonel Hugh Curbishley - Christopher Benjamin
 * Robina Redmond/The Unicorn - Felicity Jones
 * The Hon. Roger Curbishley - Adam Rayner
 * Greeves - David Quilter
 * Davenport - Daniel King
 * Professor Peach - Ian Barritt
 * Miss Chandrakala - Leena Dhingra
 * Mrs Hart - Charlotte Eaton

References to Agatha Christie novels & short stories

 * Donna mentioned Miss Marple and the story of the murder in the Orient Express before Agatha Christie has written about them, and may therefore have inadvertently caused the creation of them.
 * Another potential influence occurs when the Doctor is poisoned and Christie is heard to utter the words "sparkling cyanide", which happens to be the title of her well-known 1945 novel.
 * The Colonel faking his inability to walk and the Unicorn posing as Robina Redmond are ideas taken from the Christie novel After the Funeral.
 * Lady Eddison is depicted reading The Murder of Roger Ackroyd, an early Agatha Christie novel where the murderer is actually a doctor.
 * Novel titles referenced in the episode are:
 * Dead Man's Folly : Miss Chandrakala's description of the Professor's book (as in 'a dead man's folly'; not the actual name of the book)
 * The Body in the Library : Donna's remark about the professor's death
 * Cat Among the Pigeons : a servant's remark about the murder
 * Nemesis : Agatha's nickname for the murderer
 * The Secret Adversary : Agatha's nickname for the murderer
 * N or M? : the Doctor's question to Agatha about the piece of paper she found
 * Murder on the Orient Express : Donna mentions it to Agatha Christie, unaware that the book hasn't been written yet
 * Why Didn't They Ask Evans? : the professor's remark before he dies is "Why didn't they ask... heavens" (the book's title refers to the murder victim's last words)
 * They Do It With Mirrors : Agatha's explanation about the giant wasp, believing it to be a hoax
 * Appointment with Death : Lady Eddison says Chandrakala had "an appointment with death" when mourning over her death
 * Cards on the Table : the phrase the Colonel used when he asked Agatha about what she knew about the mystery
 * Sparkling Cyanide : Agatha Christie says after detecting cyanide in the lemonade
 * Crooked House : How Agatha describes the history of Eddison Manner
 * Endless Night : how the Doctor describes the current murder mystery
 * Taken at the Flood : Lady Eddison said "He was taken at the Flood", referring to her Vespiform lover
 * The Moving Finger : the Doctor phrases "the moving finger points" when interrogating the suspects
 * The Murder of Roger Ackroyd : the book Lady Eddison was reading when the Firestone activated
 * Death Comes as the End : Agatha says "Death comes as the end, and justice is served" after Golightly's death
 * The Murder at the Vicarage : the Doctor says "Murder at the Vicar's Rage" after Golightly's death, though he believes it could do with some work
 * Yellow Iris (a short story included in The Regatta Mystery and Other Stories ): at the dinner where the Doctor spikes the soup with pepper, there is a vase of yellow iris as a table centrepiece. It was later expanded to novel length as Sparkling Cyanide.
 * In Russell T Davies' rewrite of the script, he inserted a reference to Ten Little Ni**ers (also known as Ten Little Indians and And Then There Were None), but deleted it.