Name – Cassandra O'Brien Dot Delta Seven
Species – Human?
Planet – Earth/New Earth
Temperament – Murderous
Appearances –End of The World, New Earth

Cassandra first appeared as a piece of skin with a face in the middle stretched on a frame with a brain in a vat below. She claimed to be the last pure human, kept alive by extreme cosmetic surgery. She hatched a plan to hold the VIP guests of Platform One to ransom and when that failed, tried to kill them all. The Doctor thwarted her plans.

When we meet her again, she is hidden in the basement of the hospital on New Earth, tended to by a force grown clone called Chip. She takes over Rose's body and the brain and skin in the frame dies so that she cannot go back.

Death - First death - Dried out and exploded having raised the temperature on Platform One.

Second death - Cassandra's consciousness in the body of Chip died of heart failure, comforted by her younger, Human self.

Human Cassandra

Human Cassandra and Chip Cassandra