Original air dates 2 September – 23 September 1978. This entire season makes up one arc, “The Key To Time”.
The Doctor and K9 are off to a holiday when the TARDIS is diverted and the doors open and a great voice says The Doctor is needed.
A/The Guardian pulls The Doctor off to collect the Key To Time, a power too dangerous for any being to posess. They Key must be returned to the Guardian before the Universe is plunged into Eternal Darkness. Doctor also gets an assistant. The White Guardian tells the Doctor to prevent the Black Guardian from getting the Key to Time.
Romana is the assistant and the Doctor is not impressed, despite her being quite impressive.
Off they go for the first part!
Two men in furs are stealing something.
Two other men arrive to consider purchasing the planet.
Doctor and Romana find the Key part; it’s part of the crown jewels, which are heavily guarded. Romana is stuck in a trap while the Doctor tries to unlock the jewels. Credits roll as they try and rescue her!
They find the added rock in the crown jewels and realize the whole shaggy dog story the guard told is just that.
Doctor figures out enough of their plan.
Planet Buyer finds a hidden mic, and it makes him suspicious.
Doctor and Romana interrupt robbery and escape the guard, but meet up with Planet Buyer at the entrance to the castle. The Planet Buyer plans on shooting them as the credits roll.
They are held by Planet Buyer who threatens them. Doctor summons K9 for help.
Palace Guards search for the stolen gold. The Guards do a casting of the bones to find the missing gold. The Seeker moves to the area to seek again. Planet Buyer plans to steal the rock and get his money back.
Doctor rigs a radio to call the second man, who’s still hiding. K9 zaps guard and door, Doctor, Fraud Seller, and Romana head towards the place second man is hiding.
The Seeker seeks again, and sends them to the Catacombs, and gives up. Catacombs are full of bloodthirsty monsters. Everyone converges there looking for the rock and the gold. Doctor, Romana, Fraudster, and K9 hide while Planet Buyer comes in after them. Someone makes a noise and sets of the guards. Credits roll.
Doctor blows his dog whistle and one of the giant monsters comes.
Everyone hides. Planet Buyer goes back to town to get the Seeker to find the fugitives.
Second Man sends his sidekick back to the city to Fraudster.
Doctor sneaks back to find Second Man and the stone, which turns out to be the Key part they need. Fraudster stole the tracker they’re using to find the stone, and runs away.
Doctor hides as one of Graf’s guards. Romana and K9 search for Second Man and the stone.
Palace Guard blows up the entrance to the catacombs. One of Fraudster’s men is killed, leaving him upset.
Romana finds Fraudster, reunites with them. Doctor tricks Prince into blowing himself up, swapping a bomb for the stone.
Doctor and Romana retreat to TARDIS, convert stone to Key part. Credits roll.