The Three Companions is a 12 part mini-series which will be on the main Doctor Who range as a bonus feature starting in Spring 2009. Each episode lasts 10 minutes long making a 2 hour play in total.
Plotline
The three companions are Anneke Wills returning as Polly, Katy Manning as Jo Grant and John Pickard as Thomas Brewster. On modern day Earth, Polly tracks down Jo Grant and realises that their travels with the Doctor have intersected. Whilst the planet is in the midst of an enviromental catastrophe, a third companion Thomas Brewster is watching them in possesion of a stolen TARDIS.
It was confirmed on the Big Finish Christmas Podcast that part 1 will feature on The Magic Mousetrap.