A Cyber-Lieutenant assisted a Cyber-Leader in an attempt by an army of CyberIsomorphs to acquire the Nemesis in November 1988. With a fleet of thousands of Cyber-Warships, the Cybermen intended to acquire the Nemesis and transform Earth into New Mondas.
The Cyber-Lieutenant objected to the Cyber-Leader making reports to the Cyber-Fleet, to which the Leader said the Lieutenant was "outside [its] function."
The Cyber-Lieutenant, along with another Cyberman, attempted to kill Ace when the Seventh Doctor fired the rocket-sled's engine at them, destroying the Lieutenant and its comrade. (TV: Silver Nemesis)