Leela was unlike any other companion the Doctor had ever had before: a ruthless, savage warrior who would kill without a second's hesitation. When the people on her home planet decided to settle their differences and live in peace (The Face of Evil), Leela had concluded that life with the Doctor would be more exciting. The fourth Doctor attempted to 'civilise' her but Leela somehow resisted the Doctor's attempts. In the end, Leela fell in love with one of the Chancellery Guards on Gallifrey and decided to stay (The Invasion of Time)

Louise Jameson is has returned as Leela in the a third series of Gallifrey for Big Finish