15 Best Companions In Doctor Who History
12. Nyssa (Sarah Sutton)
Nyssa first appeared in the Fourth Doctor story The Keeper of Traken and joined the TARDIS crew alongside Tegan in Logopolis after the Master murdered her father and wiped out her entire planet. It was one of those days.
Nyssa was the gentler side of the Fifth Doctor's wayward associates. She even seemed to have patience for Adric. Nyssa was another genius whose expertise sorted out a large number of problems. She was also a dab hand at piloting the TARDIS, not to mention refereeing the ongoing stramash between the Doctor and Tegan.
Nyssa decided it was time to move on in Terminus after helping to cure people dumped on Terminus of Lazar's disease. Hers was another departure that rather depressed the famously vulnerable Fifth Doctor.