Cara was a Time Agent. She had a reputation for unorthodox methods, which included being willing to kill those she considered 'obstructive' even if they were only unable to help her because they legitimately didn't remember what she was looking for.
She came back in time to try and capture Magnus Greel for his crimes, but temporal drift resulted in her arriving a few years after her intended target date.
She sought records about Greel, starting at the Docks and then at his digs, killing the officials who hindered her efforts when their only crime was not remembering what she was after. She then found out about Li H'sen Chang. She was brutal in her methods. She went to the Palace Theatre to find more information about Chang and discovered that Henry Gordon Jago had booked his act. She came to the Red Tavern to find Jago and killed one of its regulars. She then tortured George Litefoot for information about Greel. She attacked Mrs Hudson, Litefoot's housekeeper. When she discovered that Magnus Greel was dead she was distraught because she couldn't kill him herself. Her vortex manipulator exploded and killed her. (AUDIO: The Stuff of Nightmares)