England, 1826--the toil and drudgery of the coal miners is emphasized with the opening elegiac music. Jack Ward and his companions go to the bath house to wash, but suddenly, gas seeps through the walls, sending them to unconsciousness. They reemerge alive, but with red circles under their ears, and acting violently. They kick a food stand, knocking down its contents and a young boy.
The Doctor and Peri are en route to Kew Gardens, but the TARDIS is pulled of course to 1826. There, they try to find the source of the time disturbance and trace it to the Rani, who like the Master is a renegade Time Lord and an old classmate.
This is a semi-historical story, as they meet George Stephenson, the engineer whose Blucher locomotive hauled coal from Killingworth colliery. The Doctor tells Peri: "How would you like to meet a genius?" She says, "I thought I already had."
The Rani, who has been taking the brain fluid enabling men to sleep throughout history, treats humans as "walking heaps of chemicals." "There's no place for the soul in her scheme of things." Result: the men become restless and violent. When the Doctor argues that humans haven't done any harm to her, she counters with: "They're carnivores. What harm have the animals in the fields done them, the rabbits they snare?... Do they worry about the lesser species when they sink their teeth into a lamb chop?" Point to the Rani there. She's so callous, the Doctor angrily tells her "They should never have exiled you. They should have locked you in a padded cell!"
The Master is also here. Not only has he improved his compressor so that its victim totally vanishes, he wants to use the Rani's skills to continue his feud with the Doctor. The Rani has nothing but contempt for the Master and even mocks the rivalry between them: "It obsesses you to the exclusion of all else.", "You're unbalanced--no wonder why the Doctor always outwits you." She even says of his schemes: "It'd be something devious and overcomplicated. He's be dizzy if he tried to walk in a straight line." Indeed, the Master is a bumbler here compared to the clever and efficient Rani. I wouldn't want to tangle with the Rani.
The interior of the Rani's TARDIS alone is worth watching this episode, as is a feature of it revisited at the end of The Two Doctors. Let's see, goofs and other things: The cliffhanger to Part 1 is effective, there's a small added scene when the cliffhanger is repeated in Part 2, which elicits a "Oh, come on!" Peri has a nice apricot dress, but as for that yellow top... urgh! And the Luddite riots ended in 1816, a decade earlier.
Kate O'Mara makes the Rani more formidable than the Master and easily carries this story. Other honors go to Gawn Grainger as Stephenson and as Terence Alexander as Lord Ravensworth, head of Killingworth. One of the Sixth Doctor's best stories, with the harsh 1820's replicated remarkably well.