Vicki comes from the twenty-fifth century, where she grew up near a large field and a castle with a drawbridge. After losing her mother, her father was taking her back to Earth when their spaceship crashed on the planet Dido. There he was killed, along with the rest of the crew, leaving Vicki an orphan. When the Doctor offered her a place on his ship, she was happy to accept.
As she comes from a time far in advance of Ian and Barbara's, Vicki finds them rather antiquated. Not only do they think classical music like the Beatles is fashionable, but Barbara teaches subjects like reading, writing and arithmetic that Vicki learned in nursery school! When Vicki was ten years old, she had earned a certificate of education in such subjects as medicine, physics and chemistry - although her education, administered by machines one hour a week, did not include such medieval cures as aspirin.
Vicki tries very hard to be adult and cope with situations in the best way that she can, but inside she can be really quite frightened. Her travelling companions usually sense this, and can sometimes be rather patronizing with her. Vicki sometimes resents the fact that they think of her as a child, but she is grateful for the comfort they offer. Vicki also worries about her place in the TARDIS crew, particularly whether or not she is useful to them. But she is not entirely helpless - Vicki is actually quite plucky, and once she sets herself to a course of action, she is determined to finish it. She is also quite the optimist.
Vicki has very acute hearing for certain sounds that others may not even be able to detect (which is ironic, since Vicki is not a very good whistler). She enjoys exploring, but is terrified of heights. She is fairly short, with shoulder-length blonde or light brown hair and light-colored eyes. She usually wears a short, dirt-repellent black dress with a zigzag collar, and black tights. Poor Vicki sometimes ends up having to dress as a boy when she travels into the past.
Her travels with the Doctor finally came to an end when, during a visit to the ancient city of Troy, she found herself falling in love with a man named Troilus. When Troy was destroyed by the Greeks, Vicki decided to stay behind, change her name to Cressida, and stay with Troilus to rebuild the city.
