Kaftan was a member of the Brotherhood of Logicians. Along with her colleague, Eric Klieg, she financed Professor Parry's expedition to Telos. The Logicians secretly hoped to form an alliance with the Cybermen.
However, when Victoria came to, she tried to force herself past Kaftan too the controls. The Logician drew her gun but was attacked by a Cybermat that knocked her unconscious.
When Kaftan awoke, the Doctor and the others had exited the tombs beneath. For their scheming Klieg and Kaftan were locked in the weapon testing room. There, they re-purposed a cyber-gun so they could use it.
Kaftan tried to use it against the Cyber-Controller, and discovered too late that the Cybermen had never planned on allying themselves with the Brotherhood of Logicians, deeming such things "have no value," but was killed by him. Toberman mourned her death, which helped him regain his senses after falling under Cyberman control. (TV: The Tomb of the Cybermen)