Dr Genevieve "Geni" Marceau was a French physicist on the Fortitude. She was a part of Lord Barset's expedition to find Barset's grandfather's ill-fated 1929 expedition to Antarctica, which had been attacked by terrestrial lizard men.
In 2012, Geni, Ben Hodgson and Professor Kelvin McIntyre discovered the London police box-shaped TARDIS that was trapped under the Antarctic for millions of years. Geni took the TARDIS key that was still in the door and pocketed it. When the Seventh Doctor, who was also trapped under the ice, was revived, Geni nursed him back to health. Meanwhile, Lord Barset and his men began awakening the Ice Warriors trapped under the ice, led by Lord Arakssor. After the Doctor realised the trouble everyone was in for awakening the Ice Warrior war criminals, he, Ben, Mac and Geni escaped in Aristo One.
When Aristo's battery began running low, the four were forced to abandon the vehicle and travel on foot. They tried calling The Fortitude with little success until Arakssor shut off Geldar's distress signal. When rescue arrived, Geni tried waking Mac, but was unable to. The Doctor commandeered Blade One to stop the Ice Warriors, and Geni boarded as well. Ssrongar attacked Blade One with the sonic cannon and the helicopter crashlanded. Discovering the TARDIS at the expedition's dig site, the Doctor and Geni were able to contact an Ice Warrior warship on the other side of the galaxy by reactivating Geldar's distress signal and boosting it. The Martian commander, Red 0089, discovered the message, and, upon recognising Arakssor, bombarded the prison from orbit. The Doctor and Geni quickly rushed to safety in the TARDIS as the rogue Martians were wiped out, and Geni was dropped off back on The Fortitude. (AUDIO: Frozen Time)