"We have been colonising other planets for a thousand million years..." Two years have passed since the Nestene creature vanished from UNIT's top secret Warehouse... Suddenly and without warning the Nestene strikes, once again using Autons as its deadly foot soldiers. As mysterious UNIT operative Lockwood struggles to unearth the Nestene plan, he finds himself drawn to remote Sentinel Island. There, the population have been caught up in a bizarre frenzy of religious activity.