Polly (Anneke Wills)
Polly was the secretary of Professor Brett, who had developed a malevolent computer called WOTAN. Personable, and strong-willed, Polly had recently befriended a despondent sailor, Ben Jackson.
The Doctor defeated WOTAN and the tank-like mobile War Machines it commanded. The Doctor accidentally took off with Polly and Ben on board, leading them into a series of adventures, including the Doctor's first encounter with the Cybermen.
Ben and Polly were present when the Doctor regenerated for the first time. When their travels eventually returned them to contemporary Earth, Ben and Polly took the opportunity to leave.