Name: 'Ace' is her nickname. She's ashamed of her real name, and only told Mel in a moment of intimacy. (I feel that she would only ever tell another girl; not a man or a boy - probably not even the Doctor.) Her real name is Dorothy I didn't specify a surname; it can be either the surname of Dorothy in The Wizard of Oz or something that works in the context of the story it appears in - or, more likely. she'll just avoid the question and keep it secret.
Age: At the point of her appearance in Dragonfire, she was meant to be sixteen years and eleven months In fact. she's based on three girls I know. all of whom are fourteen, so she has the personality and maturity of a young rather than middling) teenager.
Home: She comes from Perivale, which she regards as the pits of London. As far as she's concerned, the only good thing about Perivale is that it has two tube stations! (One of the girls she's based on actually said this while watching a recording.)
Family: She doesn't have any brothers or sisters. If she did, she'd have mentioned them in her intimate speech to Mel. Besides, she's too much of a loner inside She didn't get on with her parents, and she gets angry simply at the mention of them. Sometimes she refuses to accept that she even has any parents; at other times she wants to believe that her 'real' parents - the kind, loving ones - are somewhere else, maybe on another planet. But however bad a picture she paints of them, the truth is that her parents are an ordinary middle-class couple who always kept their feelings hidden, and didn't know how to cope with their tearaway daughter.
School: She enjoyed chemistry and was taking it at A-Level - although she would probably have failed because she isn't the academic type. She got suspended from school when she blew up the art room.
History: While she was at school she also had a boring evening job working in a fast-food cafeteria. She also used to do experiments with explosives in her bedroom. and it was an accident with one of these that triggered a time storm and carried her to Iceworld - where she again found work as a waitress.
Speech: She uses phrases typical of London teenagers: 'Wicked!', 'Well worth!', 'Naff!' and of course 'Ace!' I don't care if, technically she left Perivale in early 1987, and so ought still to be using the phrases of that period; the more current and realistic her speech, the better. She coins nicknames for everybody, such as 'doughnut' for Mel, and 'bilgebag' for Glitz. And even though it irritates the Doctor, she can't help calling him 'Professor'. The only time she reverts to using real names is when she's frightened, as when Kane was holding her hostage in Dragonfire.
Personality: Typical teenager really. Bright and full of life one moment, spiky and argumentative the next. Even though she likes the Doctor she's bound to come over all moody and complaining with him from time to time. A particular characteristic is her heightened sense of excitement, which sometimes overrides her sense of danger: her immediate reaction on first seeing the creature in Dragonfire was to yell with delight, and only later did she think to run like hell!
From the Script writer's guide.