A woefully underrated story and easily one of Mark Gatiss’ very best episodes, my favourite since The Unquiet Dead. He is playing to his strengths with the Victorian era setting, summoning a really beautiful story in a season which has lacked stories with this level of clarity of thought.

Diana Rigg and daughter provide the story excellent antagonists, giving it a unique flavour. When you add to this another outing for the fabulous Paternoster Gang and the horrific surprise that is Mr Sweet, you get an incredibly unique production.

The look of the story is stunning. Some victims in bell jars, others who are blood red. Empty factories with giant gramophones engineering fake noises. Blood sucking parasites. It’s a truly wild story. And a brilliant showcase of how to do a Doctor and companion lite story - by giving over the first 14 minutes to Strax, Jenny and Vastra. It makes Matt and Jenna’s reveal all the sweeter.

How could it be better? The villainous plan could be slightly tighter - it doesn’t share the same vision as the rest of the story. Also - the season arc truly gets in the way, with Artie and Angie randomly popping up at the end ahead of Nightmare in Silver. They are wielding unlikely photos of Clara throughout time that have come from… somewhere? An unwelcome distraction.