love affair. Davies summarised the relationship between the two characters as "soul mates" who "understand and complement each other". Lynette Porter, in her book Tarnished Heroes, Charming Villains and Modern Monsters: Science Fiction in Shades of Gray on 21st Century Television observed that Rose's role "humanizes the Doctor and makes him less alien, not only to other characters, but to the audience". In the first series finale, Rose takes on deadly energies to save the Doctor and planet Earth. Script editor Helen Raynor felt the episode gave Rose a chance to "again be the Doctor’s equal" and "to finally match him with a gesture that is so noble, and strong, and heroic, and clever". Davies describes Rose in the context of this scene, and the whole of the first series, as being "braver than brave and more loyal than anyone else in the universe". The Doctor repays her loyalty by sacrificing his ninth incarnation in turn to save her; Davies states unequivocally that "he gives his life for her". Elements of Rose's characterisation in the first series were originally different. Paul Abbott was scheduled to write an episode which would have revealed that Rose's entire life had been manipulated by the Doctor in order to mould her into an ideal companion. Davies wrote the episode "Boom Town" to replace it when Abbott realised he was too busy to work on the script. With the Tenth Doctor In an interview with SFX producer Phil Collinson stated that after the Doctor regenerates the "initial dynamic changes because [Rose] has to learn to trust him again". Piper added that as the Doctor is incapacitated Rose consequently feels "unloved", "isolated" and "like she's lost her best friend". In the Doctor's absence Rose relies on her observations of him and tries to mimic his actions. Collinson felt it was important to resolve any mistrust between the pair by the end of the Christmas Special, as the public had responded well to Rose and the Doctor's friendship previously. Davies had scripted dialogue in "The Christmas Invasion" explaining the newly regenerated Doctor's estuary English accent by stating he had imprinted on Rose and adopted her way of speaking. However, due to time constraints this sequence was not filmed. Discussing how Rose had developed by the second series, Piper described her as having "come on in leaps and bounds" and stated she is now "a lot more proactive."