One of Lupton's men tries to run, but the spider blasts him down with a bolt of energy. She tells Lupton she will give him the power he seeks. She jumps on his back and disappears, having joined with his mind. He dismisses the others.
The Doctor looks at a record of Clegg's thoughts when he died. The screen is filled with images of spiders. The Doctor decides to look into the crystal himself.
The spider tells Lupton she came to find the Doctor's crystal. They concentrate and locate it in the Doctor's possession.
The Doctor finishes gazing into the crystal. All he saw was the face of a hermit who was his mentor in his youth.
Mike sends Sarah off to alert the Doctor and tries to speak to the abbot, K'anpo, but is stopped by Tommy. After he distracts Tommy, he is then stopped by Lupton.
The next morning, Sarah tells the Doctor her story as he examines the crystal. He is uninterested until she tells him about the spider. He's puzzled as he never encountered giant spiders on Metebelis III. He speculates that they came from a later time.
Lupton comes to UNIT and knocks out a guard and Benton to reach the Doctor's lab. He uses his powers to teleport the crystal to his hand. The Doctor, the Brigadier, Benton and Sarah give chase. Lupton steals the Doctor's car and they chase in Bessie and a helicopter. Lupton then hides and then steals the helicopter. But the Doctor follows in his car, which flies through the air.
Lupton lands and steals a boat. The Doctor follows in a hovercraft. He manages to get beside Lupton and jump onto the boat. But Lupton has vanished!