Elth of Balhoon

The Elth of Balhoon was the Moxx of Balhoon's brother. He believed that the survivors of Platform One hadn't tried to help the Moxx and had abandoned him to die, and decided to kidnap them to get his revenge. The Doctor and Rose Tyler discovered his plan and rescued his the prisoners. The Doctor convinced the Elth that they had done all they could to save him but it was too late. (DWBIT: Reunion of Fear)