Doctor Who Battlefield: Part Four (1963–1989) watch online HD

Morgaine forces Ace and Shou Yuing to hand over Excalibur by threatening to release the Destroyer, so the Doctor and the Brigadier enter a dimensional portal to stop her.

The Brigadier was supposed to be killed off in this episode, a move fully supported by Nicholas Courtney, Andrew Cartmel and John Nathan-Turner. However, Ben Aaronovitch couldn't bring himself to kill off such a beloved character.

The Doctor's speech decrying nuclear weapons originally ran much longer and was trimmed down.

Ben Aaronovitch's vision of the Destroyer of Worlds had to be scaled back. The writer wanted the Destroyer to start off as merely a man in a business suit, who gradually became more demonic as the serial progressed. This would have been both too expensive and too time consuming to achieve, and so the Destroyer appeared in his monstrous form throughout.

This is to date the final episode recurring since Doctor Who and the Silurians: Episode One (1970) appearance of the Doctor's beloved yellow Edwardian car, Bessie since his 3rd, 4th and 7th incarnations. It is still unknown if the car will turn up in future episodes of Doctor Who (2005-Present).

This episode was watched by 4 million viewers on its original transmission.