When the base was taken over by Ice Warriors, they ordered Phipps to assist Fewsham in repairing the damage Osgood had done to T-Mat. Instead he and Locke repaired the video link to Earth to warn them of the invasion. Locke was killed, but Phipps escaped and hid within the base. In the solar energy room, Phipps developed a trap that used solar power. With this he killed an Ice Warrior. The solar power also allowed him to radio the Second Doctor, Zoe Heriot and Jamie McCrimmon as they landed on the Moon.