Revealing Mistake: When the guards fire at the Doctor in the patrol vehicle, the shots are shoulder height, but the explosion they cause is near the ground.
Revealing Mistake: When the Doctor releases Peri from the transmogrifier platform, the buckle of the restraining belt breaks off and slides to the bottom of the platform.
Quillam: I see you have a keen interest in the flora of Varos, Doctor.
The Doctor: Just a passing fancy.
Chief Officer: It'll pass faster than you think. Kill them!
Arak: No more executions? Torture? Nothing?
Etta: It's all changed. We're free.
Arak: Are we?
Arak: What should we do?
A very violent story with the acid bath killings and hangings in this episode singled out for criticism.