Cut and pasted from the Radio Times website:
The people of a Victorian Yorkshire mill town are terrified when bodies start washing up from the river, bright red and wax-like - but with the Doctor and Clara nowhere to be seen, it's up to lizard detective Madame Vastra - last seen in 2012 Christmas special The Snowmen - and her sidekicks Jenny and Strax to take centre stage as they attempt to get to the bottom of the mystery. It seems the answer lies behind the imposing gates of Sweetville mill, owned by the plain-speaking Mrs Gillyflower.
This episode is penned by Mark Gatiss.
Follow the links to the Radio Times features on this episode:
This is the trailer: