The Metaphysical Engine , or What Quill Did ( TV story ) The Metaphysical Engine , or What Quill Did was the seventh episode of the first series of " Class " . It saw Miss Quill get her arn removed , as promised by Dorothea Ames in " Brave - ish Heart " . This episode takes place during the events of the preceding story , " Detained " . Whilst the previous episode was " Quill - lite " , this episode featured almost nothing of the students and instead focused on Quill . It revealed that she held more of a grudge against the Rhodian s than she did towards the Shadow Kin , and that she intended to get revenge on the only remaining Rhodian . It also revealed a more sinister side to the Governors , as they forced Quill to kill a new found friend and suggested that they were expecting Quill to have died from the surgery of removing her arn . It is also the first episode in which the Coal Hill Space - Time Rift s do not make an appearance . Synopsis . 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 . Plot . 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 . 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 . Story notes . Ratings . Final UK Ratings : 0 . 68 million Filming locations . " to be added " Production errors . " to be added " Home video releases . DVD releases . " to be added " Blu - ray releases . " to be added "