Josephine Grant

Jo Grant joint UNIT by the help of her uncle in the United Nations, and she was introduced to the Doctor as his new assistant by the Brigadier. She was eager to prove herself, but she was accident-prone and she helped the Doctor with his work. She ruined one of his experiments and nearly narrowly avoided blowing the Doctor up. Jo and the Doctor got on well and she was frequently terrified by aliens, especially the Master. Jo left the Doctor when she met Professor Jones, and the Doctor was upset when she left.

Jo Grant was in The Terror of the Autons to The Green Death.