After being let down by Echoes of Grey, I am glad to say that this one was excellent. The atmosphere was on point, the characters vivid, the plot and problem engaging, and the twists were great. I particularly enjoyed how the Doctor's usual practices did not pay off this time, the unusual time period and place the story is set in, and the final twist, which I did not see coming and which I thought was very clever, highlighting Zoe's character and cunning. Recommended!