Casp

Matron Casp was the leader of the Sisters of Plenitude. She controlled the experiments on the new humans in the Intensive Care Unit beneath New New York Hospital in the year 5,000,000,023. Casp used the experiments to cure other patients in New New York Hospital, where she was Matron. The hospital had great success in curing patients, but the existence of the new humans was kept a secret. Casp tried to divert the Tenth Doctor from the unit, but Cassandra O'Brien, inhabiting the body of Rose Tyler, discovered the unit and led the Doctor to it. After rendering the Doctor unconscious, Cassandra demanded money from the Sisterhood in exchange for not informing the NNYPD about their criminal activities. Casp refused, and in response Cassandra let free the Intensive care patients. This resulted in the quick death of Casp's colleague Sister Jatt.

Casp put the hospital under quarantine and then disappeared. She attempted to flee from the infectious patients by climbing up a lift shaft ladder in pursuit of the Doctor and Cassandra/Rose. She grasped Rose's ankle and berated them for ruining the Sister's work, to which Cassandra responded by telling her to "go and play with a ball of string". However, when a patient grabbed Casp's ankle, spreading its numerous viruses to her immunity-free body, Casp fell from the ladder and plummeted to her death at the bottom of the shaft, screaming all the way down. (TV: New Earth) Personality and traits

Outwardly, Casp appeared benevolent and kind, expressing polite confusion when the Doctor noted the lack of a hospital shop. However, she was rather cruel, cold and calculating, as she was the one who came up with the concept of using new humans as test subjects for diseases and cures. She could also turn violent, as demonstrated when she threatened Cassandra. She did not regard weapons as necessary due to possessing claws, stating "Why bother with arms, when we have claws?" before unsheathing them with a hiss. She did not regard the test subjects as living creatures, acting surprised when they showed signs of intelligent life and ruthlessly incinerating them when they did.