Martha Jones (clone)

Martha Jones was cloned from the original Martha Jones in order to help the Sontarans to start a war with Earth. As her first job was to deactivate the missiles that were going to get fired at the Sontaran Ship. She then assisted the doctor (Unknown to him that she was a clone). And she tried to stop him from going to the room with the Cloning Pool. But he found out that she was a clone a woke Martha up. But the Clone Martha died infront of the original Martha. Saying that she was sorry for what she had done. (DW: The Sontaran Stratagem/The Poison Sky)