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This story was never produced.

Therefore, its known narrative elements are not a part of the Doctor Who universe as we, on this Wiki, choose to define it. It may have been the basis for a similar story in another medium, however — and that story may indeed be valid.

The Ultimate Evil was a story planned for Season 23. It was to be written by Wally K Daly, and directed by Fiona Cumming.

It was released in 1989 as a Target novelisation, written by Daly himself. 30 years later, in 2019, it was adapted as an audio adventure produced by Big Finish Productions, again adapted by Daly from his original scripts.

Plot background[]

The story would have been set on the holiday planet Tranquela, where Dwarf Mordant had been using a space ray to make all the good people raging killers.

The TARDIS would have arrived on the planet. Peri would have been attacked and left for dead, while the Doctor would have temporarily fallen under the Dwarf Mordant' powers.

In the end, the Doctor would have Mordant use an antidote ray on the planet before Mordant escaped. (DOC: The Lost Season)


  • This story was adapted into the novel The Ultimate Evil.
  • Originally, it is one of the three stories not adapted into Big Finish's Lost Stories series from the original Season 23 as Big Finish could not reach an agreement with Wally K. Daly to produce the story. The rights were since rectified and an audio adaptation released on 14 November 2019.