Bonnie (The Zygon Invasion)

Bonnie was the leader of a radical Zygon faction which opposed the ceasefire between Humans and Zygons.

Biography
She originally lived in one of the Zygon colonies, this particular one being located under Clara's block of flats. The Zygons kidnapped Clara, and Bonnie took on her form, pretending to be Clara while she went around England with Jac looking for more clues to the Zygon uprising.

While Bonnie (still in Clara's form) led Jac and some UNIT soldiers into the Zygon colony, she dusted off the Zygon pods in which they were keeping the kidnapped humans. Jac quickly deduced that Bonnie was not actually Clara and that it was the humans that were in the pods. Bonnie ordered her fellow Zygons to kill them.

Later, overlooking the sea, Bonnie prepared to fire a missile launcher at Boat One with the Twelfth Doctor and Osgood inside. The Doctor attempted to reason with her over the phone, but Bonnie, despite the Doctor's protests, fired a missile at the plane. (TV: The Zygon Invasion) When Bonnie and Kate were about to detonate the Osgood Boxes, the Doctor berated them both, going into a massive tirade on how he is still suffering from the effects of the Time War. After agreeing to not detonate the "Osgood Box" that would unmask all Zygons on Earth, Bonnie assumed Osgood's form and acted as the second protector of Earth. She felt that she and Osgood were a credit to both humans and Zygons and planned to take on the role of protecting the Earth from threats. (TV: The Zygon Inversion)

Personality
Bonnie was mentally unstable and seemed to suffer from emotional suppression. She often bottled up her feelings, resulting in a calm and cold demeanor but also had an explosive temper. She was smug and sadistic, saying that she was looking forward to hearing Clara scream and smiling as she watched her fellow Zygons murder Jac and her soldiers. Bonnie seemed to consider murder and war to be a game and was eager to cause bloodshed.

However Bonnie was also childish and when angry, she had a tendency to smash things. Her childishness was also shown when the Doctor pointed out that she didn't actually know what she wanted to do if she took over the world. Having not actually thought that far ahead, Bonnie was unsure how to respond and the Doctor managed to talk her out of starting a war by telling her he forgave her. Bonnie felt remorseful and couldn't understand how the Doctor could forgive her. Feeling she had to try and make up for her crimes, Bonnie became Osgood's "sister" and decided to help her protect the Earth.