The Doctor and Jo make their way back to the tunnels so they can travel back and stop Shura, only to run into an ambush that the Controller has set up. The Doctor convinces the Controller that he has the means to stop the Daleks before they have even begun, and the Controller lets him go, only to be betrayed by an interrogator and exterminated by the Daleks. The Daleks send a strike force to the 20th century to ensure that their version of the future is preserved, and, with the Ogrons, attack as the delegates arrive at the house. In the ensuing battle between the Daleks, Ogrons and UNIT, the Brigadier evacuates the delegates. The Doctor, back in the present, makes his way down to the cellar to try to convince Shura not to activate the dalekanium bomb; Auderly House is empty, and it will all have been for nothing. However, once Shura hears that the Daleks and the Ogrons are entering the house, he tells the Doctor and Jo to leave. The Brigadier tells his men to fall back to the main road as the Daleks and the Ogrons search the house for the delegates and Styles, with the Daleks intent on carrying out their mission of destroying the peace conference. Shura detonates the dalekanium bomb, destroying both the house and everything in it.