Amazon.com description: Product Description
: An epic six story set celebrating 20 years of Doctor Who at Big Finish! Time is collapsing. Incidents of chaos and devastation are appearing throughout the lives of one Time Lord and his many friends -all fallout from one terrible disaster.From Earth's past and present to timeless alien worlds, from the cloisters of Gallifrey into the Vortex itself...The Doctor must save universal history -and he needsall the help he can get. This special release to celebrate 20 years of Doctor Who at Big Finish is a limited edition pressing of just 4,000 copies, and contains two Behind the Scenes discs. Six hour-long stories see characters from the entire history of Doctor Who crossing paths - some for the very first time! Professor River Song (Alex Kingston) meets her predecessor, another time-travelling archaeologist, Professor Bernice Summerfield (Lisa Bowerman). Kate Stewart (Jemma Redgrave) travels back in time to classic UNIT and meets the Third Doctor (voiced by Tim Treloar) and Jo Grant (Katy Manning). CAST: Tom Baker (The Doctor), Peter Davison (The Doctor), Sylvester McCoy (The Doctor), Colin Baker (The Doctor), Paul McGann (The Doctor),Tim Treloar (The Doctor),Sophie Aldred (Ace), Lisa Bowerman (Bernice Summerfield) ,India Fisher (Charlotte Pollard),Karen Gledhill (Allison Williams),John Heffernan (The Nine), Anna Hope (DI Patricia Menzies), Louise Jameson (Leela), Alex Kingston (River Song), Katy Manning (Jo Jones),Ingrid Oliver (Osgood), Jemma Redgrave (Kate Stewart), Hugh Ross (Sir Toby Kinsella), Pamela Salem (Rachel Jensen), Georgia Tennant (Jenny), Lalla Ward (Romana), Simon Williams (Group Captain Gilmore). More cast details to follow. .