THE TARDIS MATERIALISES IN A WINTRY LANDSCAPE of deep snow and chilling winds, bringing the Doctor, Jamie and Victoria to the external perimeter of a vast, plastic, protective dome. The travellers have landed on Earth at some unknown point in the future. They discover that the dome encompasses a Georgian mansion of wood-panelled corridors and neo-classical statuary, containing an advanced scientific base. The Doctor detects a problem with the pitch of the equipment and realises that he and his friends have arrived in the middle of a major crisis. The Doctor immediately assumes control of the situation, discovering the base’s chief scientist, Penley, has abandoned the project after difficulties with Clent, the base’s single-minded and ambitious director.
Meanwhile, a small expedition to the face of a nearby, steadily advancing, glacier uncovers a huge, armoured corpse in the ice. Believing it to be prehistoric, the investigative team brings its archaeological treasure back to Britannicus Base. However, the Doctor realises that the armour has electronic components.