Following Lupton, Sarah is transported to Metebelis 3 where she is captured by the human villagers. The Doctor uses the TARDIS to follow Sarah, but the spiders are waiting. Is this adventure one too many for the Doctor?
Mike Yates (who left UNIT after his involvement in the affair with the Dinosaurs) contacts Sarah-Jane about mysterious goings on in a Buddhist retreat in the English countryside. Soon it becomes apparent that an extraterrestrial force is attempting to reclaim a crystal the Doctor 'borrowed' from Metebelis 3.
A highly intelligent spider from Metebelis 3 arrives on Earth in search of the powerful crystal. When it is stolen from his laboratory, the Doctor leads the chase over land, water and air to recover it.
With the Doctor in a coma, his only hope of survival lies with a device inside the TARDIS. But Sarah is captured by the spiders and is held prisoner in their larder.
