Petronella Osgood's flat

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By the time that Petronella Osgood was working as UNIT's scientific advisor, she was no longer living at her family's house but in a messy flat on the fifth floor of a building. A cat that lived next door sometimes tried its luck by scratching at her door. (AUDIO: Death in Geneva)

Osgood took Kate Stewart, the Fourth Doctor and Sarah Jane Smith to her flat to collect a temporal iterator abandoned by the Third Doctor which she had been working on. (AUDIO: Past Lives)

Osgood sometimes took UNIT artefacts home to work on when deadlines were looming. She took Jay Roy there to explain to him what UNIT was and to offer him a job as her assistant, but they were attacked by the Tengobushi and Jay sacrificed himself to save her and Josh Carter by detonating a plasma grenade. The flat was destroyed. (AUDIO: Power Cell) As she had never been attacked at home before, Osgood found the experience especially disturbing. (AUDIO: Death in Geneva)