The Pyralis Effect (audio story)

The Pyralis Effect was the fourth story of the fourth series of The Companion Chronicles, produced by Big Finish Productions. It was written by George Mann, narrated by Lalla Ward and featured the Fourth Doctor, Romana II and K9 Mark II.

Publisher's summary
Long ago, the planet Pavonis IV was saved from certain destruction by the Doctor. Now it is dead, laid waste by environmental catastrophe, but a few survivors and their precious race bank survive on the starship Myriad. Their mission: to scour the universe for the fabled dimensionally transcendental obelisk in which their saviour travels, and persuade him to save their world again.

As the TARDIS arrives, by chance, on the Myriad, the Fourth Doctor and Romana are just in time to see the crew achieve their goal. Or so they think... Death stalks the corridors of the ship, the artificial intelligence CAIN has lost control, and a force is about to be unleashed that threatens the entire galaxy.

Plot
to be added

Cast

 * Romana II - Lalla Ward
 * Suri / CAIN / The Pyralis - Jess Robinson

Continuity

 * The Myriad has a race bank. (TV: The Hand of Fear, Underworld)
 * The TARDIS's arrival onboard the Myriad was chosen by the randomiser. (TV: The Armageddon Factor)
 * Romana isn't sure she wants to return home yet, but would later be called back to Gallifrey (TV: Meglos) before accidentally entering E-Space. (TV: Full Circle)