Vortex Ice (audio story)

 was the first of two stories comprising the two hundred and twenty-fifth release of Big Finish's monthly range. It was written by Jonathan Morris and featured Colin Baker as the Sixth Doctor and Lisa Greenwood as Flip Jackson.

Publisher's summary
In search of "exotic particles", the Doctor and Flip arrive 700 feet underground, in a mine in Northern Mexico – only to run into a scientific expedition. Among their number, an exobiologist. They're all on the hunt for alien life! Deep underground, the team finally uncovers a cave of vast crystals – like ice, despite the heat. And inside the crystal: something frozen. Something trapped in time. If only it were something simple, like a monster. But it's far, far worse than that.

Plot
to be added

Cast

 * The Doctor - Colin Baker
 * Flip - Lisa Greenwood
 * Sai Chopra - Shobu Kapoor
 * Dylan Argent - Orlando Seale
 * Holly Whitfield - Katherine Senior
 * Jannik Woolf - Monty D’Inverno

Worldbuilding
to be added

Continuity

 * The Doctor refers to artron energy. (TV: Four to Doomsday)
 * The Doctor states that Gallifrey is "just to the left" of Karn. (TV: The Brain of Morbius)