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Doctor Who and the Power of Kroll was a novelisation based on the 1978 television serial The Power of Kroll.

Publisher's summary[]

The huge, octopus-like Kroll lived deep in the swamps of the humid, steamy planet.

To the native swamp-warriors, Kroll was an angry, mythical god. To the money-grabbing alien technicians, Kroll was a threat to a profit-making scheme.

In their search for another segment of the Key to Time, the Fourth Doctor and Romana have to face the suspicion of the Lagoon dwellers, the stupidity of the technicians and, finally the power of Kroll ...

THE POWER OF KROLL is a novel in the Key to Time Sequence. Also available THE RIBOS OPERATION, |THE STONES OF BLOOD and THE ANDROIDS OF TARA.

Coming soon:


Chapter titles[]

  • Prologue
  1. The Swamp
  2. The Gun-Runner
  3. The Sacrifice
  4. The Tunnel
  5. The Thing in the Lake
  6. The Attack
  7. The End of Harg
  8. The Storm
  9. Escape Through the Swamps
  10. The Rocket
  11. Countdown
  12. The Power of Kroll
  • Epilogue

Deviations from televised story[]

  • A prologue explores the Kroll's feeding cycle and how the creature slept for centuries while fed on the nutrient-rich mud before being disturbed by the building of the refinery.
  • The moon is named as Delta Three.
  • Thawn mentions having brought Harg back some book tapes.
  • Romana is described as wearing bright orange rather than red and black.
  • The Swampies believe Romana is a spy.
  • Thawn mentions having four crew rather than five, with the hovercraft pilot being omitted.
  • Skart is said to be the Swampies' high priest.
  • Rohm-Dutt (whose name is written as Rohm Dutt throughout) has a dream of being pursued by the Swampies and attacked by Kroll.
  • There is no mention of the Sons of Earth wanting to go back to Earth, just stopping human colonists expanding to Delta Three.
  • Dugeen confirms he is a member of the Sons of Earth, sent to sabotage the Refinery. His reaction to Thawns's crack about them being a crank organisation is more angry than the televised version.
  • The Swampie killed by Kroll in the marshes is trying to get on the Doctor and Romana's boat rather than on the bank.
  • The Swampies make no effort to save Ranquin from Kroll's tentacle and leave the refinery after the Doctor stops the launch.
  • The Doctor suggests that Fenner share the food and supplies left in the refinery with the Swampies. In the novelisation, Fenner actually looks through the stores, considering the idea.

Writing and publishing notes[]

  • Then producer John Nathan-Turner expressed the view that he thought the cover artwork poor. The image of Tom Baker on the original edition is taken from his expression after defeating Kroll and obtaining the fifth segment of the Key to Time in the original story.

Additional cover images[]

British publication history[]

First publication:

  • Hardback
W.H. Allen & Co. Ltd. UK
  • Paperback


This Target Book was released as an audiobook on 7 October 2021 complete and unabridged by BBC Audio and read by Geoffrey Beevers.

The cover blurb and thumbnail illustrations were retained in the accompanying booklet with sleevenotes by David J. Howe. Music and sound effects by Simon Power.

External links[]