Doctor Who: The Fourth Doctor

The hugely powerful Key to Time has been split into six segments, all of which have been disguised and hidden throughout time and space. Now the even more powerful White Guardian wants the Doctor to find the pieces. With the first segment successfully retrieved, the Doctor, Romana and K9 trace the second segment of the Key to the planet Calufrax. But when they arrive at exactly the right point in space, they find themselves on exactly the wrong planet - Zanak.

In the great maze of the Powe Complex dwells the dreaded Nimon, a fearsome monster with immense scientific powers. The Nimon has promised to restore the Skonnan Empire to its former glory. But first it demands sacrifice - youths and maidens from the peaceful planet Aneth. The TARDIS collides with the spaceship delivering the victims, and the captured Romana is condemned to be sacrificed to the Nimon. Aided by the faithful K-9, the Doctor goes to the rescue. In the heart of the maze he confronts the Nimon and uncovers a terrifying plot to enslave the galaxy.

Whole civilisations are threatened in these four classic TV novelisations featuring the First, Fourth, Tenth and Eleventh Doctors.

In Marco Polo, by John Lucarotti, the TARDIS breaks down in Central Asia in the year 1289, causing the travellers to meet an intrepid Venetian explorer. In The War Machines, by Ian Stuart Black, the Doctor senses a powerful and sinister force around London's newly built Post Office Tower. In The Faceless Ones, by Terrance Dicks, the Doctor and his friends are drawn into a web of intrigue and deception at Gatwick Airport. In The Ambassadors of Death, by Terrance Dicks, the Doctor and Liz investigate the disappearance of three astronauts after their space capsule returns to Earth empty.