Dinosaurs are all over London as Professor Whitaker initiates ‘Operation Golden Age’.
The dinosaurs start fighting each other. Finch arrives and tries to take the Doctor, but Benton and the Brigadier arrive as well and take the Doctor away.
They confront Grover and Whitaker. The duped environmentalists from the fake spaceship also appear, along with Sarah. They demand an explanation. In the ensuing fight Whitaker and Grover are transported back through the time machine to the “Golden Age” they sought to bring to modern Earth.
Back at UNIT HQ, the Brigadier confirms that the crisis is over, but there are still human casualties to deal with. Finch will be court martialed. Yates is offered the chance to resign and given extended sick leave. The Doctor reflects that people like Grover may have had good motivations in wanting to fight pollution and environmental degradation, but they took their schemes too far and endangered all mankind and its civilization. He decides it is time for a holiday and offers to take Sarah Jane to the holiday planet of Florana.