Ep 13. State of Decay: Part 1

The Doctor and his companions, Romana and K-9, find themselves on a desolate planet where an ancient civilization was destroyed by a mysterious force. They soon discover that the planet is being controlled by three powerful beings known as the Great Vampires, who feed on the life force of others.

As they explore the planet, the Doctor and his companions come across a group of humans, who have been living in fear of the Great Vampires for generations. The humans are ruled by a mysterious figure known as the Three Who Rule, who claim to be the vampires' servants.

The Doctor and Romana soon realize that the Three Who Rule are actually vampires themselves, who have been using the humans as cattle to feed on. They also discover that the vampires are planning to launch an attack on the rest of the universe, using a spacecraft that was left by the ancient civilization.

With the help of the humans and a renegade vampire, the Doctor and Romana set out to stop the vampires from completing their plan. However, they face many obstacles along the way, including the Three Who Rule, the vampires' army of warriors, and the dangers of the planet itself.

State of Decay: Part 1 is a thrilling episode that sees the Doctor and his companions facing some of their greatest challenges yet. With its eerie atmosphere, gripping storyline, and memorable characters, this episode is a must-see for any fan of Classic Doctor Who.