The shootout between Scarlet and Goddard posed a number of challenges for the effects crew. To simulate a line of bullets hitting the castle wall, a strip of Cordtex explosive was fixed to the set and lit at one end, creating a series of miniature explosions as the flame travelled down the strip. The destruction of the battlements was achieved by filling the scale model, which was made of balsa wood and polystyrene, with petrol gel and igniting it. For the shot in which Scarlet is gunned down, the puppet was fitted with its "grimacing" head that was originally created for the series' first episode.