The Doctor and Professor Slade are aided in their escape by McEvoy, who brings them skimmer craft (Sky-bikes). With the creature still in pursuit, the Doctor leads them to a faint energy pulse he has detected. It comes from what appears to be an underground city abandoned by Corah's once mighty civilisation. The City turns out to be a weather control station, built to stop a great drought, but it didn't work. The creature pursuing them has adapted over thousands of years to absorb moisture and water.