Ep 6. The Age of Steel

In this episode of Doctor Who, titled "The Age of Steel," the Doctor and his companion Rose find themselves landing in a parallel universe where Pete Tyler, the father of Rose's deceased father, is still alive and successful. However, they soon discover that this alternate world is far from perfect, as it is ruled by the ruthless Cybermen.

The Cybermen have converted a large portion of humanity into Cybermen themselves, stripping them of their emotions and free will. The Doctor and Rose team up with a group of rebels, including former employees of the company that helped create the Cybermen, to stop the invasion and overthrow the Cybermen's rule.

As they journey through the city, the group encounters various obstacles, including Cybermen guards and cyber-conversion factories that aim to turn more humans into machines. Along the way, the Doctor discovers that the Cybermen's leader, John Lumic, plans to take the cyber-converted humans to another planet in order to start a new civilization of Cybermen.

Despite setbacks and betrayals, the Doctor and his companions push forward in their quest to stop the Cybermen. In order to do so, they must work together to create an electromagnetic pulse that will disable the Cybermen and their conversion facilities.

The episode builds to a tense climax as the rebels launch their attack on the Cybermen, using the EMP to disable their weapons and machines. The Doctor confronts Lumic in a final showdown, ultimately revealing the dark consequences of his actions and putting a stop to his plans.

Overall, "The Age of Steel" is a thrilling episode of Doctor Who that explores the darker side of science and technology, as well as the importance of standing up against oppression and tyranny.