Bertram (The Lamentation Cipher)

"Bertram" was the name that Charlotte Pollard gave to a Viyran otherwise known as the Rogue Viyran.

The Lamentation Cipher
Bertram spoke differently to the other members of his species and was light on his feet. He told Charlotte Pollard that the Viyrans didn't know much about the Ever-and-Ever Prolixity. He knew of the Lamentation Cipher. (AUDIO: The Lamentation Cipher)

He infected Charley with a virus that would reboot the Viyrans. He allowed her to escape so it would incubate in her and make it more virulent. (AUDIO: The Viyran Solution)

The Identical Men
The Rogue Viyran dispersed Charley and Robert's pod in order to cushion their arrival and ensure their survival. His own molecules were also dispersed, but he managed to recombine himself at Department 001 and rejoined Charley and Robert, telling them that the Identical Men that confronted them were too dangerous to take on. (AUDIO: Embankment Station) He used his ruffling power on them, causing him to exhaust himself.

Charley and Robert carried the Rogue Viyran to safety and named him "Bertram", a name that he accepted. He told the humans that he believed that the Prolixity had brought them to this time and place due to the presence of something analogous to a virus being present, the Prolixity having latched onto his own purpose for being. They were later taken into police custody and transported to Woking, who unwittingly invigorated Bertram with an MRI and held them at gunpoint when they tried to flee. (AUDIO: Ruffling)

Bertram carried Woking to safety after he collapsed and impeded the Identical Men that came for them by absorbing the electricity in the London Underground's rail. He identified the Identical Men's pulse as some sort of coded message, one which did not affect him nor Charley and Robert, and told his friends that he believed he could feel the Prolixity inside him and that this had given him his ruffling power. When they returned to Embankment tube station and fled from the Identical Men, Bertram was able to make himself, Charley and Robert disappear. (AUDIO: Seed of Chaos)

Joining the Proto-Viyrans
Bertram, Charley and Robert found themselves tied up in the Gelrasians' web, where Bertram transformed into a Gelrasian. The Prolixity returned him to the 21st century where he asked Woking and the Prime Minister if anything had changed, suspecting that Charley and Robert might have changed history, which they seemed not to have done. He asked Rab to respond to Charley's message with a request to know who Charley wished to speak to, to which she answered that she wished to speak to Bertram as he was already with her on Gelrasi ten years after her arrival.

Bertram teleported away and went to Gelrasi on a Proto-Viyran ship. Upon arriving on the ship, he took on their appearance and understood their aim to protect life from itself through culling by means of the Identical Men. After ten years, he reunited with Charley and Robert, whom he asked not to call him "Bertram", and told them the truth of their work and that of the Proto-Viyrans. To prevent their knowledge doing harm to the Proto-Viyran cause, he shot at the two of them, although he did apologise and Charley was apparently saved by the Prolixity. (AUDIO: The Destructive Quality of Life)

Appearance
Outside of his Viyran suit, Bertram had skin which looked like wet tissue paper. (AUDIO: Embankment Station) Upon absorbing the Prolixity and arriving on Earth, he transformed to a more human form (AUDIO: Seed of Chaos) and took on the form of a Gelasian in the Gelasi web and a Proto-Viyran on their ship. (AUDIO: The Destructive Quality of Life)