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Professor Bernice Summerfield and the Crystal of Cantus, or simply The Crystal of Cantus, was the twenty-eighth Bernice Summerfield audio story released by Big Finish Productions. It was the fifth and final story of the sixth season. It was told unconventionally through voice-overs and flashback-style point of view scenes.

This story also featured the Cybermen, as the cover art (and dialogue in-story) indicates Cybermen of The Tomb of the Cybermen-era. It is notable for its gruesome revelation of how the Cybermen create Cybermats: from babies.

The story reveals Irving Braxiatel's motivations and manipulations (particularly of Jason Kane) that began in the 2003 story Professor Bernice Summerfield and the Mirror Effect.

Publisher's summary[]

Fabled crystals from long-dead civilisations. Jason Kane blundering into situations out of his control. Entombed Cybermen waking from a century-long sleep. It's all in a day's work for Professor Bernice Summerfield. Armed with her endless supply of witty quips and penchant for alcoholic beverages, she'll find the Crystal, rescue Jason, destroy the Cybermen and be home in time for supper.

Except, this time, it's different. This time, as the saying goes, it's personal.

And, after this adventure, things will never be the same again.


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  • The story is not told in a conventional narrative but rather with voice-over and flashback-style point of view scenes.
  • Commander Hallan is a recurring character in the Gallifrey audio series, which also features Braxiatel in a major role.


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