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The Metaphysical Engine, or What Quill Did was the seventh episode of Class. It was written by Patrick Ness, directed by Wayne Che Yip, and featured took place during the events of the preceding story, Detained.


With the gang trapped in detention and out of the way, Miss Quill accepts Dorothea's astonishing offer: to help remove the arn from her head, so she can finally reclaim her freedom.


Charlie, Ram, April, Tanya and Matteusz are out of the way in detention. Before leaving, she tells them she has things to do and does not want to be disturbed. She then locks them in the classroom, and goes to see Dorothea in the school hall.

Dorothea warns her that if they proceed with the operation to remove the arn, Quill may die. Quill states that she wants to either die or have freedom. As they are discussing, a man named Ballon arrives and Dorothea says that they can begin. She takes out a device and they are all miniaturised and transported inside it.

They arrive in a mysterious forest that is clearly not on Earth. Dorothea orders Quill to remember her earliest childhood memory while Ballon charges into the forest, returning with a dead animal, which he reveals to be an arn, the first step to removing the arn in Quill's head. Dorothea explains that the device is a metaphysical engine, capable of transferring individuals into a thought or belief, in this case, the "idea of" the heaven of the arn.

Dorothea activates the device again, sending the trio to the version of hell believed by the Ballon's species, the Lorr. He reveals that he is a shape-shifter who is frozen in one form. Here, Quill and Ballon encounter the devil of the Lorr, from whom they must extract blood. Ballon fears the being, but Miss Quill consoles him with her people's concept of the "first fear" that they must overcome. Meanwhile, Dorothea contacts the Governers, claiming that the mission is not going as planned. Ballon manages to overcome his fear and extracts the blood from the being, freeing his hands.

Finally, the trio must obtain the brain of a Quill so Ballon can learn their anatomy. They travel to the idea of Quill heaven (despite Quill claiming such a place cannot exist) and encounter the birth of the Quill goddess. Quill attacks the goddess, furious at her for allowing her people to die. The goddess attempts to speak to Quill, however Ballon decapitates her before she can, later claiming he believed the goddess was Quill's first fear and he wanted to help her as she helped him. Quill begins to feel the arn causing her pain, which Dorothea states is due to her believing the surgery will work.

Dorothea Ames activates the metaphysical engine

Dorothea activates the small device.

Having obtained all the necessary materials, the trio return to Coal Hill. After practising on the goddess' head, Ballon successfully removes the arn from Quill's brain. Although she is in extreme pain and has severe disfigurement to her face, Ballon uses the flesh of the Lorr devil to 'heal' her skin, resulting in a long scar being visible on her face but all other injuries removed. After announcing that she is proud of the scar, as it was a mark of honour for a soldier, she realises she is attracted to Ballon and the two have sex. After they wake, they notice that Dorothea is absent, and explore the school to find her. They eventually find their way to a vast desert where Dorothea is standing. Dorothea announces that 'Coal Hill' was simply an illusion and they are actually in the Cabinet of Souls. She also announces that she has actually left and that she is appearing by hologram only. She tells them the Governors only expected one of them to survive, and as such only provided enough energy for one of them to escape the Cabinet. She suggests that a fight to the death will be necessary, given the warrior status of their respective races. She provides Quill with her gun, and informs Ballon that the Governors have located his niece (the only other living member of his species) on Earth. She also warns that time passes faster in the Cabinet, and they may die of old age within a day if they do not escape.

Although they initially try to resist, they eventually realise they must fight or they will both die. Ballon overpowers Quill and takes the gun. Quill demands that he shoot her with honour. He fires the gun, however Dorothea tricked them and made the gun shoot the person holding it rather than the person they are aiming it. Quill is devastated at Ballon's death and buries his body in the sand. As she stands to leave, the souls of the Rhodians appear to her, and she announces that she wishes for them to be dead.

She returns to the real Coal Hill and discovers that she has aged several months at least, however she has only been absent for 45 minutes in real time. She then returns to the classroom, and where the students are. She tells them about the Arn and then collapses. However, we also see that Quill is noticeably several months pregnant.



General production staff

Script department

Camera and lighting department

Art department

Costume department

Make-up and prosthetics


General post-production staff

Special and visual effects


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.


  • Miss Quill mentions cat-obsessed people on the Internet.
  • Dorothea tries to touch a hiding plant.

Coal Hill Academy[]



  • Quill refers to the Zygons as "zygotes".
  • Ballon is a Lorr.
  • Ames says that now Quill can "force a certain Prince to wipe the Shadow Kin from the grinning, smirking face of the universe".


  • Quill refers to the poet on Earth and quotes her poem, "Home", as saying, "no one leaves home unless home is the mouth of a shark."





  • Ames has a machine that is metaphysical in nature. Quill claims that metaphysics are just thought and theory.




Story notes[]

  • "Bad Girls" by M.I.A. plays over the final moments of the episode.
  • The story takes place during the events of Detained, and the beginnings and endings of both episodes are the same scenes, only this time told from Quill's perspective.


Final UK Ratings: 0.68 million

Filming locations[]

to be added


Date Time Channel Notes
Monday 30 January 2017 22:45 BBC One except Northern Ireland & Northern Ireland HD
Monday 30 January 2017 23:40 BBC One Northern Ireland & Northern Ireland HD only

Production errors[]

to be added


Home video releases[]

DVD releases[]

  • The Metaphysical Engine, or What Quill Did was featured in the series one DVD boxset, which was released in the UK (Region 2) on 16th January 2017, followed by a Region 1 release on 11th July. The Region 1 release contained an additional blooper reel and various deleted scenes that were not present on the Region 2 release.

Blu-ray releases[]

to be added

External links[]