The TARDIS deposits the Doctor, Tegan, Turlough and their android ally Kamelion aboard a prison ship.
A ship with just one prisoner: Nustanu, last warlord of the Zamglitti - monstrous, mind-bending mimics able to turn themselves into mist.
A ship that's in trouble, and about to make a crash-landing - on a planet of mists!
Since Doctor Who, Peter Davison's appeared in shows such as The Last Detective and Campion, while London stage appearances include Legally Blonde and Spamelot.
He's been reprising his role as the Fifth Doctor for Big Finish since 1999.
Jon Culshaw comes on board to play Kamelion, a shape-changing android companion from the Fifth Doctor's era, the character's first appearance at Big Finish.
Mark Stricksonand Janet Fielding worked together as the Doctor's companions in 1983 and 1984, and this most recent run of adventures for them have been long anticipated by fans Cast: Peter Davison (The Doctor), Janet Fielding (Tegan), Mark Strickson (Turlough),Jon Culshaw (Kamelion), Anjella Mackintosh (Orna), John Voce (Rako), Simon Slater (Nustanu).