For the final battle sequence between the Renegade and Imperial Daleks, the BBC Effects Department's pyrotechnics were so loud and the explosions so realistic that the London Fire Brigade was dispatched to the scene by local residents who feared that an IRA bomb had gone off. Sylvester McCoy recalled that after the first explosions, a number of car alarms in the neighborhood went off, and the emergency services drivers were surprised when they arrived to see Daleks coming at them from out of the smoke.
This was the final Dalek story of the original series. The Daleks had a brief cameo in Doctor Who: The Movie (1996) and the Daleks finally returned in Dalek (2005). Davros finally returned in The Stolen Earth (2008) /Journey's End (2008), which actor Julian Bleach took over the role from Terry Molloy.
Last serial of the original series to feature Davros and the Daleks.
In the original script, The Doctor destroys the Black Dalek in episode four with a gun which had been stored alongside the Hand of Omega (originally, the Hand of Rassilon). This was intended as a parody of the quick-draw tradition in Hollywood westerns, but it was felt to be too out of character for the Doctor, particularly by Sylvester McCoy.
In the rehearsal script, Gilmore (now planning to retire) refered to his group as the Special Incursions Counter-Measures Unit and that the army wanted to take over. He said they had "some bright boy, Captain Tunbridge-Steward or something, worked for the SOE during the war" to put in charge. If included in the final episode, this would have contradicted a large number of older UNIT and Brigadier stories.