Vastra

Vastra was a female Silurian warrior who shared a house at 13 Paternoster Row with Jenny Flint, her maid and subsequently her wife, in Victorian London.

Early life
Vastra was one of many people who owed the Doctor a debt; she had awoken during the construction of part of the London Underground and had wanted to take revenge on innocent tunnel workers for the deaths of her "sisters". After Vastra had slaughtered at least five commuters, the Doctor convinced her not to give in to rage. (TV: A Good Man Goes to War)

The battle of Demon's Run
At the behest of Scotland Yard, she tracked down and ate Jack the Ripper in 1888. Immediately thereafter, she was summoned by the Eleventh Doctor to help rescue Amy Pond and her baby from Demon's Run. She and her maid and future wife Jenny Flint, arrived at Demon's Run with an army of Silurian soldiers. She called the Doctor 'old friend,' and judging by how well she seemed to know him and the fact that she said she owed the Doctor a "very old debt", they must have known each other for a long time. He had told her about Time Lords; she referred to regeneration, the Untempered Schism and the time vortex. Vastra and Dorium Maldovar realised that Melody was human with some Time Lord DNA and then also realised that their enemies had given up too easily. Leaving the Doctor in the control room, they went to meet up with the other remaining members of the Doctor's army.

Meanwhile the Headless Monks were sneaking through Demon's Run, subtly slaying the Doctor's army as they headed for the TARDIS. Thanks to Lorna Bucket, Vastra, Jenny, Strax, Rory and Amy had some warning about the trap and were able to prepare to battle the Headless Monks. After Dorium got himself beheaded by trying to negotiate with them, the monks attacked. Vastra weilded both of her swords with great skill and precision, effortlessly defeating any Monk brave or foolish enough to challenge her. She survived the battle without any injury and Jenny also made it through alive, although Lorna and Strax died. Following the battle, Melody Pond's adult self, River Song, arrived and transported Vastra and Jenny back to London and Vastra and Jenny's home era, via Vortex manipulator. (TV: A Good Man Goes to War)

Although Strax was dead, an unspecified friend of the Doctor resurrected him and he became Vastra and Jenny's butler. (TV: The Great Detective, The Snowmen)

Female Sherlock Holmes from the dawn of time
At some point during the next four years, Vastra married Jenny. (TV: The Snowmen)

Vastra, alongside Jenny and the Sontaran Strax, later summoned the Doctor for help. The Doctor refused, claiming he had "retired." (TV: The Great Detective)

In December 1892, Madame Vastra was contacted by Felicity Gregson due to her expertise as the Great Detective. Felicity told her about light with trailing smoke and fire that fell from the sky behind her house. She claimed that the crash site had been cleaned overnight, but she still had physical evidence to show Vastra in person. Vastra planned to meet Felicity in Ranskill Gardens, but due to being double booked at the Greek Embassy, she sent Strax instead. Unfortunately, Felicity was murdered before Vastra had a chance to inspect her evidence.

After returning home, Vastra met with Harry, who had helped to discover Felicity's body in the snowman he'd built with his friend Jim. After her true appearance initially caused him to run out of Pasternoster Row, she gained his trust by saving his life alongside Jenny and Strax. She also paid Mr. Ranskin, the man Harry worked for, to become his new guardian to ensure his protection from the people that wanted him dead. With the help of Jenny, Strax, and Harry, she discovered that Felicity's evidence had been a wisp of fog, which was actually part of an alien force that took a fog-like form and planned in invade Earth and blot out the sun. They were defeated with snow. (PROSE: Devil in the Smoke)

Defeating the Great Intelligence
Vastra and Jenny later confronted Walter Simeon about his institute and Vastra found that Simeon was using snow which possessed a telepathic field, allowing it to build itself into lethal Snowmen by mirroring the thoughts of people around it. She noted that it could be a terrible weapon but Simeon casually told her that he was planning to take over the world, saying that there was nothing she could do to stop it. As he left Vastra called after him that even if she couldn't stop him she knew someone who could and Simeon replied that he was looking forward to meeting him.

Vastra was later visited by Clara Oswald, whom she treated with some suspicion at first, and Strax even implied that Vastra thought of Clara as a prisoner by saying she would be "obliterated" if she tried to escape. Vastra and Jenny forced Clara to do the "One word test" where she would only be allowed to answer questions with a single word so that Vastra would know she wasn't lying. Clara eventually used the word "Pond", the previous surname of the Doctor's former companion Amy, before she married Rory Williams. Impressed that Clara had figured out how to pursuade the Doctor to help and convinced of her honesty, Vastra called the Time Lord and told him that Strax knew where he should begin his investigation. She then sent Strax to see if the Doctor needed any help but the Doctor sent the Sontaran away.

Vastra and Jenny later turned up on the doorstep of Captain Latimer's house where they were greeted by Alice who screamed at the sight of "the lizard woman from the dawn of time" and then fainted when Strax went over to try and calm her down. Ignoring the maid, Vastra and Jenny quickly informed the Doctor that Simeon was causing the alien snow to spread over Latimer's estate. Meanwhile Jenny used a force field to trap the Ice Governess, who had been created from the drowned governess who had frozen in Latimer's pond a year earlier. Vastra then teased the Doctor about missing all the action he had been avoiding since the deaths of Amy and Rory and the Doctor told her to shut up.

While the Doctor and Clara lead the Ice Governess up to the roof, Vastra, Jenny and Strax remained in Latimer's office to protect him and his children. After hearing a loud thump outside, they saw Clara lying in the snow with the shattered remains of the Ice Governess around her; the Ice Governess had basically committed suicide in order to cause Clara to fall to her death. The Doctor arrived in the TARDIS and took Clara's body inside where Strax managed to bring her back to life. Vastra went to the Doctor and told him that Clara's injuries were severe and that she was going to die. The Doctor refused to accept the loss of another companion, especially so soon after losing Amy and Rory, and left the TARDIS, asking Clara if she would travel with him if he saved the world. Clara agreed and the Doctor confronted Simeon who was waiting at the front door. He and Vastra then took the TARDIS to Simeon's institute with Vastra wondering why the Doctor was suddenly doing everything he could to save the world again. The Doctor explained that the Universe owed him for all the times he had saved it and that if he saved the world, he hoped that the Universe would let Clara live. Although Vastra doubted that the Universe made bargains, she went with him and they met Simeon in his office. After the Doctor erased the memories of Simeon's adult life with a Memory worm, the Great Intelligence took control of Simeon's body and knocked Vastra too the ground before she could strike it with her sword. Simeon then attacked the Doctor but collapsed as the snow inside the giant snowglobe in the office turned to rain. Simeon died and the Great Intelligence fled, having learned to survive without a physical body.

Realising that the rain was caused by the grief of the Latimer family and by Clara's tear as she lay dying, the Doctor and Vastra rushed back to the house. Strax sorrowfully informed them that Clara only had a few moments left. The Doctor told the dying girl that they had saved the world together and assured her that he wouldn't go back to moping on his cloud. Clara died only seconds before midnight and the clock chimed informing everyone that it was Christmas Day.

Vastra and Jenny were at Clara's funeral where they discussed the Great Intelligence with the Doctor. The Doctor then went to Clara's grave and learned her full name, Clara Oswin Oswald. Delighted by the revelation, the Doctor told Vastra and Jenny that he had met Clara before and that she had died twice, causing him to believe that there was another version of her somewhere in the Universe. Leaving the confused Vastra and Jenny in the graveyard, he ran to the TARDIS intending to search for his new friend. Vastra thought that maybe the Universe was rewarding the Doctor for once more saving the world, commenting that maybe it did make bargains after all. (TV: The Snowmen)

Personality
Although Vastra enjoyed eating humans, she had a romantic relationship with Jenny and eventually married her. Vastra could control her darker urges, and she spared two men when she and Jenny were helping the Doctor despite commenting she was hungry. She poisoned one of them with her venom, but this was only to stop him from calling for help. When her sisters died in hibernation, Vastra was enraged, but with the Doctor's help she controlled her anger and did not seek revenge on the humans who had awakened her.

Vastra was a fierce warrior who wielded two swords in combat. She held her own against a group of headless monks, surviving without any apparent injury. She was very loyal and protective, ordering her allies to protect Melody Pond at all costs. Vastra was an old friend of the Doctor and seemed to know him well. However, although she supported the Time Lord, she disagreed with his decision to stay out of the affairs of the Universe. Although she understood that he was heartbroken and told Jenny that heartbreak affected everyone, she also felt that he had spent too much time sulking on his cloud and was therefore delighted when the Doctor returned to save the world.

Vastra showed a considerable understanding of time and space and even the Time Lord's themselves, knowing about the Untempered Schism, regeneration, and even how the Time Lords became what they were, which was through prolonged exposure to the Time Vortex. She also believed that the Universe did not make bargains but was less sure when the Doctor gleefully told her that Clara was still alive in another timeline after her death. (TV: A Good Man Goes to War, The Snowmen)

Vastra was very honest, brutally so at times, and was determined to make everyone around her be honest too. In her opinion, the truth could be said in one word, while lies were just a string of words. Therefore she used the "One word test" to ensure that people were telling the truth. When Clara fell from a cloud, Vastra was sorrowful but bluntly stated that she was dead, making no effort to soften the impact Clara's death would have on the Latimer family, who had all been very fond of her.

Vastra's investigative exploits were believed have been appropriated by Arthur Conan Doyle for fictionalisation and attribution to his character, Sherlock Holmes. (TV: The Snowmen)

While she shared some of the prejudices of many Silurians against humans, saying all "Mammals" looked alike and threatening to eat one, Vastra was much more tolerant and accepting of humans than many of her species, apologising for her remarks about humans to Jenny and showing concern for the safety of the infant Melody. (TV: A Good Man Goes to War) Vastra also showed suspicion when visited by Clara and even implied that she would eat her if she discovered anything untrustworthy about her. However, she quickly warmed to Clara and was impressed when she was able to get the Doctor to return to save the world with a single word, something that Vastra, Jenny and Strax had been trying to do for ages. When Clara was mortally wounded falling from a cloud, Vastra showed concern and sorrow and later attended her funeral after she died. (TV: The Snowmen)

Spin-off?
Since their appearance, Vastra and Jenny have become quite popular among fans, with many wishing for a spin-off series of their adventures. Steven Moffat addressed this, saying he considered a spin-off when he created the two characters, but wouldn't have the time, though he would like to revisit them.

The Brilliant Book 2012
According to The Brilliant Book 2012, a book that contains non-narrative-based information;
 * She made a home in London, at first making a living as the main act in Henry Gordon Jago's "Monstre Gathering" (to the Doctor's disapproval) and then as a masked bank robber. After finding lodgings above a gin palace in Cheapside, she came across Jenny, a match girl who was being molested by a Chinese gang. She saved Jenny from the Tongs and subsequently began a relationship with her.
 * In 1881, Vastra visited Egypt and was mistaken for a god.
 * At some unknown point in Japan's history, she and Jenny battled some Cybermen.
 * Following their return to their own time, Vastra and Jenny were added to the Papal Mainframe's "most wanted" list.