The Cyber-Controller was either part of the invasion of a parallel Earth, or was cyber-converted from one of the humans stored underneath this Earth’s Piccadilly Circus as power sources. (AUDIO: Telepresence) Activated by the Machine after a dimension bridge was established to the Earth of N-Space, it followed a group of around ten Cybermen, including a Cyber-Commander, into a laboratory on Fortress Island, where it encountered Kate Stewart and Josh Carter. After they fled, it ordered the stabilisation of the dimension bridge and the activation of the Cybermen’s signalling shield by the cyber-converted Osgood. After Osgood underwent a cranial upgrade she discussed the possibility of a means to improve the dimension seeding protocols. The Cyber-Controller allowed her to complete her work before proceeding to oversee the conquest of the fort, commanding the deployment of several mobile conversion units.
Whilst the Cybermen conquered the fort, the Cyber-Controller and Osgood discussed the latter’s plan; Osgood explained that by modifying the mind control signal of the dimension bridge technology and installing it into the Auctioneers's VR app, the Cybermen could gain near-complete control of the planet within minutes. After Kate and Josh destroyed a Cyberman and a mobile conversion unit, the Cyber-Controller, under Osgood’s instruction, broadcast an update to the mobile conversion units containing Kate’s biological information so they could track her. After they were unable to find her, he then broadcast a second update to all active cyber-units to converge on the fort’s storage area, where Kate and Josh were hiding. It directly confronted Kate, and activated its secondary connection to the Cyber-Mainframe when Kate interrupted its primary connection; she proceeded to blow it up with a grenade, but underwent self-repairs shortly after.
Following this, it proceeded to converge on the laboratory with the other Cybermen, (AUDIO: Code Silver) only to discover that the War Master had arrived from the parallel Earth. After Osgood ordered a mobile conversion unit to upgrade him and Kate, it malfunctioned and electrocuted the Cyber-Controller and Osgood. Upon reactivating it ordered that the construction of cyber-conversion chambers across the planet be completed, and allowed Osgood to use the cyber-converted Vikram Shindi and Sam Bishop to locate Kate, Josh and the Master. After the two UNIT personnel had their conversions reversed by the Master in the White House Gallery, an Auctioneer base near UNIT HQ, the Cyber-Controller ordered for Osgood to undergo full conversion, believing that her intelligence was no longer useful. However, after some persuasion from Osgood, the Cyber-Controller temporarily spared her from full upgrading to allow her the chance to upgrade the Master, by modifying a mobile conversion unit to work on Time Lord physiology so that he could be upgraded.
Later, when Kate, Josh, Shindi, Sam and the Master arrived at UNIT Costermouth, they established a huge circuit around Fortress Island and used a huge electromagnetic pulse to temporarily deactivate all the Cybermen within, including the Cyber-Controller. However, they eventually reactivated when dozens of Cybermen converted from the virtually converted humans inland destroyed the circuit. The Cyber-Controller then ordered the conversions of Kate, Sam and Osgood (who at this point had had her virtual conversion reversed), only for the Master to emerge from a mobile conversion unit as the Cyber-Master, who then overthrew the Controller as commander of the entire invasion. After the Master upgraded the dimension gate to draw power from every reality, the Cyber-Controller broadcast the power upgrade to all cyber-units, only for it to short-circuit and die, along with all the other Cybermen, as the connection to all universes included the ones the Cybermen failed to begin invading, poisoning their power supply. (AUDIO: Master of Worlds)
Despite claiming to be emotionless, the Cyber-Controller displayed high levels of arrogance and underestimation of threats to the Cyber-Ideal, such as by claiming that Kate Stewart, Josh Carter and the War Master could not stop the Cybermen's invasion of N-Space, despite not knowing anything on Time Lords and therefore being unaware of their capabilities, (AUDIO: Master of Worlds) and by justifying the thousands of years it would take to fully upgrade the Cyber-Mainframe's native universe by simply stating that "the universe [was] large". The Cyber-Controller also claimed that Cyber-Technology was the most advanced technology in the multiverse, despite not having encountered highly advanced races such as the Time Lords at the time of making such a claim, nor had the Cybermen created dimension bridges to every universe. (AUDIO: Code Silver) The Cyber-Controller also believed itself to be all-powerful after having its power connection upgraded by the Cyber-Master. (AUDIO: Master of Worlds) It also displayed traces of frustration occasionally, complaining that the effects of the dimension bridge technology's mind control on humans was "so chaotic". (AUDIO: Code Silver)
The Cyber-Controller's voice was similar to the voices of the CyberMondans, (TV: The Tenth Planet) but with a deep pitch similar to the CyberNeomorphs (TV: Earthshock) and the advanced model of Cybermen of the Cyber Legions. (TV: Nightmare in Silver)