The BBC have released the synopsis for "The Crimson Horror" which will air on Saturday 4 May 2013 at a time yet to be confirmed:
There’s something very odd about Mrs Gillyflower’s Sweetville mill, with its perfectly clean streets and beautiful people.
There’s something even stranger about the bodies washing up in the river, all bright red and waxy. When the Doctor and Clara go missing, it’s up to Vastra, Jenny and Strax to rescue them before they too fall victim to the Crimson Horror!
Executive produced by Steven Moffat and Caroline Skinner
Directed by Saul Metzstein
Written by Mark Gatiss
Produced by Marcus Wilson"Journey to the Centre of the Tardis" has been confirmed to air on BBC1 on Saturday 27 April 2013 at 6.30pm.