(YATES considers.) He moves over to the DOCTOR'S monitoring equipment.) PROFESSOR WHITAKER: Of course not. SARAH tries the door but then sits in the chair to think. That's right.
Plan: A: the Doctor's equipment; Q: What does Yates sabotage to stop the Doctor from finding Whitaker's base? A: Whitaker's base; Q: What is the location of the base that the Doctor is trying to find? A: Sarah; Q: Who is in danger when the tyrannosaur escapes? Summary: Yates sabotages the Doctor's equipment to stop him finding the location of Whitaker's base but then the tyrannosaur escapes, placing Sarah in danger.