Kaftan was a member of the Brotherhood of Logicians in the 25th century. Along with her colleague, Eric Klieg, she financed Professor Parry's expedition to Telos. The Logicians secretly hoped to form an alliance with the Telosian Cybermen.
Kaftan took her servant Toberman with her and was initially unwilling to have him risk his life opening the electrified doors of the Cyberman tomb they discovered.
She drugged Victoria Waterfield's coffee so she could close the hatch to the tomb sealing Klieg, the Second Doctor and several others within.
However, when Victoria came to, she tried to force herself past Kaftan to 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 after she shot at him twice though the weapon had no effect. Toberman mourned her death, which helped him regain his senses after falling under Cyberman control. (TV: The Tomb of the Cybermen)