 The episode was primarily written by Russell T Davies after Minogue was cast . Davies described his pitch to Minogue as " busking " . The character of Astrid Peth was written for Minogue . Davies later stated that Minogue was a " very exceptional case " ; he considered writing a role specifically for one actor " dangerous territory " because the desired actor may be unavailable or decline the part . In early drafts of the episode , Astrid did not die . Davies decided Astrid 's death was necessary to allow Minogue focus on her musical career . Davies described the original nature of her death — falling over a precipice during a fight with Capricorn — as " fleeting " . He intensified the scene by changing Max from mobile to cybernetic and Astrid 's attack from an altercation to a fork @-@ lift truck . Davies felt the revised scene was " such a beautiful image " and romanticised Astrid 's " ultimate sacrifice " . 
