Paternoster Gang

The Paternoster Gang was a group of detectives active in Victorian London named after Paternoster Row, the street on which their de facto headquarters were located. (TV: The Great Detective) The group was comprised of Madame Vastra — owner of the Paternoster house — Jenny Flint and Strax.

Origin
Vastra, along with fellow Silurians, 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. At some point, she hired Jenny Flint as her maid. Vastra's relationship with Jenny eventually became romantic. (TV: A Good Man Goes to War, The Snowmen)

Vastra and Jenny were part of the Doctor's army which he summoned from across time and space to aid him in the Battle of Demon's Run. Also among the Doctor's allies was Commander Strax, a Sontaran nurse who, like Vastra, owed the Doctor a debt. He was killed in the battle with the Headless Monks. After the battle, the Doctor departed in his TARDIS, leaving River Song to take Vastra and Jenny home. (TV: A Good Man Goes to War)

However, two days after the battle, Vastra and Jenny returned to the Demons Run asteroid to retrieve Strax. They woke Strax up, informing him that he had not died since they had used alien technology to heal his wounds. Jenny said that he had never truly passed away thanks to the resurrection technology and he had been in a state of unconsciousness for two days while the resurrection device healed him. Strax was angry that his glorious death in battle was robbed from him. Vastra and Jenny announced that the station was being evacuated, and offered to take Strax with them back to London. Strax was hesitant and at first rudely refused but then changed his mind and agreed to accompany them. Joining them in Victorian London in 1888, Strax became Vastra's butler. The Paternoster Gang was formed soon after. (WC: The Battle of Demons Run: Two Days Later, TV: A Good Man Goes to War)

Defeating the Great Intelligence
Soon after the Eleventh Doctor's arrival at Victorian London to retire after losing his most beloved friends, the Paternoster Gang became known as "the Doctor's friends", and tried to convince the Doctor to return to his universe-saving career. Soon after, on 24 December 1893 the three, along with the Doctor and Clara Oswin Oswald, defeated the Great Intelligence and stopped his plan to take over the Earth using telepathic snow. During this adventure, Clara died, but the Doctor, who seemed to know her before, returned to normal. (TV: The Snowmen)

Sweetville
Some time later, a man called Mr Thursday contacted Vastra to ask her to investigate the murder of his brother, Edmund. Vastra, with Jenny and Strax, investigated Edmund's dead body, and found out a strange optogram in his eye — an image of the Doctor. Jenny was sent to Sweetville to see what's wrong, only to find the Doctor fossil in an odd red liquid. The Doctor instructed Jenny how to heal him, and once it was done, the pair went out to find Clara. They found her as a puppet inside a glass dome. The group was confused at seeing Clara, now the Doctor's companion, alive after seeing her die the previous Christmas. After Clara was recovered, the Doctor, Jenny and Clara were caught by Winifred Gillyflower, the project's manager. They were soon saved by Vastra and Strax. Then the Paternoster Gang, along with the Doctor and Clara, stopped Gillyflower's plan to launch a rocket containing a red leech poison, wiping out humanity over the Earth. Eventually, Strax shot Gillyflower, who fell to the floor and died. (TV: The Crimson Horror)

Trenzalore
Vastra was called to talk to a serial killer, Clarence DeMarco, that killed fourteen women. (HOMEVID: Clarence and the Whispermen) He told her about the Doctor's biggest secret, and gave her a space-time coordinates to him, in exchange for his freedom. Vastra agreed, and arranged a psychic conference call with Jenny, Strax, Clara and River Song. There, she told them what Clarence told her, but the call was soon disturbed by the Whisper Men who attacked the sleeping investigators. Jenny was murdered by them, but Vastra and Strax managed to wake up in time. Clara also woke up, and after telling the Doctor what was happening, the two travelled to coordinates Clara remembered. The coordinates were, apparently, Trenzalore. Vastra and Strax were also brought to Trenzalore by the Whisper Men.

There, the Great Intelligence, who controlled the Whisper Men, opened the Doctor's tomb. He jumped into the Doctor's time stream, and began to alter his history. Because of the Great Intelligence's actions, Vastra and Strax no longer knew each other. Strax attacked Vastra, and she shot and killed him. Clara reversed the recent occurrences, including Jenny's and Strax's death, by entering the timeline after the Intelligence, saving the Doctor wherever he went. The Doctor then decided to save Clara by entering his timeline himself, telling the Paternoster Gang that the TARDIS could return them home with the fast return protocol if he didn't return. (TV: The Name of the Doctor)

With the Twelfth Doctor
Having been returned to their home period, at some point they witnessed a dinosaur arrive in Thames from an earlier time. After his TARDIS was regurgitated by a dinosaur, the newly-regenerated Doctor and Clara met with the Paternoster Gang. Dealing with his new body, he was confused between Strax and Clara and later thought that she was a regeneration of Handles. After the dinosaur was set on fire and burned to death, they helped the Doctor deal with his new personality and uncover the plot of the Half-Face Man. (TV: Deep Breath)

When the Doctor visited London again with Clara, the Paternoster Gang again helped him with a new threat. They separately investigated the Carnival of Curiosities and individuals linked to Orestes Milton. They collectively learnt that Milton had enslaved two acts in the Carnival, Silhouette and Affinity and used them as weapons to escape capture from the Shadow Proclamation for war crimes. Posing as an industrialist, Milton attempted to channel anger onto the local population to turn them against each other. However, he was thwarted and promptly executed by the Proclamation. (PROSE: Silhouette)

Behind the scenes
Steven Moffat derived the name Paternoster Gang from The Brilliant Book 2012 where Clayton Hickman referred to their base as Paternoster Row. (DWM 480)