Ep 6. The Invisible Enemy: Part 2

The Invisible Enemy: Part 2 is the sixth episode of the fifteenth season of the Classic Doctor Who series. The episode is a continuation of The Invisible Enemy: Part 1 and follows the Fourth Doctor, played by Tom Baker, and his companion Leela, played by Louise Jameson, as they go on a mission to stop a virus-like enemy known as the Nucleus from taking over the universe.

At the start of the episode, the Doctor and Leela are inside the TARDIS trying to find a way to cure the infection that has taken over the Doctor's mind, leaving him susceptible to the Nucleus' control. Meanwhile, K-9, the Doctor's robotic dog, has been left on the Titan base, where the Nucleus is still spreading the infection and causing chaos.

The Doctor and Leela manage to come up with a plan to cure the infection by using a miniaturization technique to enter the Doctor's bloodstream and kill the virus from within. However, they must first get past the Swarm, a group of infected bodies controlled by the Nucleus, in order to reach the miniaturization equipment.

On the other side of the story, K-9 is working to protect the Titan base from the infected crew members and the Nucleus while also trying to find a way to help the Doctor and Leela. He creates a device that allows the Doctor and Leela to communicate with him from within the Doctor's bloodstream, which proves to be crucial in their mission.

As the Doctor and Leela navigate through the bloodstream, they encounter various obstacles such as white blood cells and antibodies, which they must defeat in order to progress. They also meet a sentient virus named the Doctor's Clone, who assists them in their mission.

Eventually, the Doctor and Leela reach the Nucleus itself, but must face a final challenge before they can destroy it and save the universe. With K-9's help on the outside and the Doctor's intelligence on the inside, they are able to successfully defeat the Nucleus and cure the infection.

The episode ends with the Doctor and Leela safely back on the TARDIS, discussing their adventure and the various dangers they faced. It serves as a thrilling conclusion to a two-part story that showcases the creativity and ingenuity of the Doctor Who series.

Overall, The Invisible Enemy: Part 2 is a compelling episode that combines action, adventure, and science fiction elements into a cohesive and entertaining storyline. It showcases the Doctor's intelligence and resourcefulness, as well as his strong bond with his companion Leela and his beloved robot dog K-9. The episode is a must-watch for fans of the Classic Doctor Who series.