Cobb (The Doctor's Daughter)

Cobb was a general encountered by the Doctor, Donna on the planet of Messaline. He was the general over Cline and the Doctor's daughter, Jenny. He asked the Doctor to join them in the war against the Hath, the creatures living on Messaline. He desired something called the source and it was his mission to get it. He had the Doctor and Donna arrested along with Jenny for not supporting him in the war. As he found out that the three of them had broke out he chased them down into the secret passage ways. Jenny was about to shoot him but did not after hearing that the Doctor said Killing makes you worse. He got into the cathedral and shot Jenny "Killing her". This angered the Doctor and Cobb was demoted and locked away.(DW: The Doctor's Daughter)