Cathica Santini Khadeni was a journalist working on Satellite Five during the time of the Fourth Great and Bountiful Human Empire. She had her brain implanted with infospike technology.
Cathica desperately wanted to be noticed for her work, especially in the Spike Room, and was appalled when Suki Macrae Cantrell was promoted to Floor 500 first. Although she was initially resistant to the Ninth Doctor's coaxing about what was actually wrong with Satellite Five, her journalistic instincts served her well. She made her own way to Floor 500 and discovered that the Jagrafess really controlled Earth, as well as the corpse of her friend Suki. She used her implanted chip to link to an abandoned Spike Room to disconnect the news feed and raise the temperature on the Floor 500. This broke the link between the Jagrafess and the zombie humans operating the computers. The creature exploded, taking the contents of Floor 500 with it, including the Editor who was prevented from fleeing by the corpse of Suki, which retained enough life to grab hold of his ankle. Cathica remained on Satellite Five, determined to return the Empire's news-gathering to more honest, investigative ways. (TV: The Long Game)