The Interplanetarian (audio story)

 was the second full story in the audio anthology 1001 Nights, the December 2012 release of Big Finish Productions' Doctor Who monthly range.

Summary
Nyssa has been possessed by a malevolent entity. Can the power of words save her?

Cast

 * The Doctor - Peter Davison
 * Nyssa - Sarah Sutton
 * Elizabeth Spinnaker - Debbie Leigh-Simmons
 * Hill - Oliver Coopersmith

Continuity

 * The Doctor uses the word "Tremas" to defeat the Interplanetarian. (TV: The Keeper of Traken)