"Episode 3 & 4 feature Souad Faress, Gregg Sulkin, Eleanor Tomlinson, Toby Parkes, Rai Rajani and Kate Fleetwood.

Meanwhile episodes 5 & 6 stars David Tennant as the Doctor, with Nigel Havers, Zienia Merton (who appeared in Doctor Who way back in 1964 during Marco Polo - playing Ping-Cho).

Floella Benjamin returns to the role of Professor Celeste Rivers for the third time in episodes 7 & 8 - and it's far from a cameo! "At last, she's going into action with Sarah Jane!" Producer Nikki Wilson reveals. Starring alongside her will be Adam Gillen (as the Professor's assistant Toby Silverman), Donald Sumpter (as Erasmus Darkening - "one of the greatest and most chilling villains we've ever seen"), Tony Boncza and Amelia Clarkson.

Also in 7 & 8 is Callum Blue - star of Dead Like Me, and boyfriend of Billie Piper's Hannah character in Secret Diary of a Call Girl.

The fifth story, made up of episodes 9 & 10, features former Coronation Street star Suranne Jones, with Jeff Rawle and Liza Sadovy.

Best of all, the same story has a cameo appearence from Lizo Mzimba - the BBC's Entertainment Corrospondent."