When the base was taken over by Ice Warriors, Slaar ordered him to assist Fewsham in repairing the damage Osgood had done to T-Mat. Instead he and Phipps repaired the video link to Earth to warn them of the invasion.
Locke managed to get into contact with Radnor and Gia Kelly, but he only managed to report that they were in desperate trouble and that Osgood was dead before Slaar discovered them and destroyed the link. Locke was then killed by one of the Ice Warriors. (TV: The Seeds of Death)