The Brigadier asks for help to discover what is causing the destruction of oil rigs off the coast of Scotland.
Sarah is attacked by a Zygon disguised as Harry who is a prisoner on the Zygon spaceship.
The Doctor and Sarah find their way into the Zygon spaceship at the bottom of Loch Ness.
The Zygon warlord, Broton, intends to use the Skarasen to attack the World Energy Conference in London.
The TARDIS takes the Doctor and Sarah to the planet Zeta Minor on the edge of the universe.
The Doctor and Sarah are held responsible for the deaths on Zeta Minor.
Lost in the universe of antimatter, the Doctor communes with the creature and makes a bargain.
Unable to escape, the Morestran probe is being pulled back to the surface of Zeta Minor.
The excavation of an ancient Egyptian tomb unleashes the Evil Sutekh, last of the Osirans.
The TARDIS is drawn off-course and lands in the country house of archaeologist Marcus Scarman.
As part of a plan to release Sutekh, the mummies are building a rocket to fire at the pyramid on Mars.
Inside the pyramid on Mars, the Doctor and Sarah Jane must solve puzzles and escape deadly traps.
The Doctor and Sarah are attacked by mysterious space suited figures and discover that the dead are walking.
Sarah Jane is taken prisoner by the alien Kraals and the Doctor discovers the truth.
The Kraals intend to invade Earth by stowing away aboard Crayford's rocket as it returns back home.
The Doctor and Sarah Jane are desperate to warn UNIT of the alien invasion, but nobody will believe them.
On the planet Karn, Dr Solon is secretly hiding the living brain of the Time Lord criminal, Morbius.
The Doctor is a prisoner of the Sisterhood of Karn who intend to burn him at the stake.
Sarah has been blinded and the Doctor asks the Sisterhood for help.
Morbius, housed in a terrifying new body, lives and breathes once more.
The Doctor learns of the discovery of two alien seed pods in the Antarctic.
Scorby and Keeler have been sent to steal the alien pod and are willing to resort to murder to cover their tracks.
The Doctor and Sarah track down the remaining Krynoid pod to the estate of Harrison Chase.
Keeler has been infected by the alien pod and is transforming into a Krynoid.
The Krynoid demands that the Doctor be surrendered to it. But the Doctor escapes to seek help.
The Doctor, Sarah and Scorby are hunted down by the mad Harrison Chase.