BBC props makers melted down 80 sex toys to use for a costume on 'Dracula'.
Bosses needed something to make up a flexible fleshy membrane on the BBC One show, and they found the only suitable material was Fleshlight, which is used to make X-rated props.
The show's writer Mark Gatiss said: "The only latex that is flexible enough is that."
What's more, Claes Bang - who plays the titular vampire - requested that his character appeared naked, because he thought it would have more of an impact on the audience.
Speaking to BANG Showbiz and other media at a 'Dracula' Q&A, Claes said: "I was the one that said he should not wear any clothes.
"It has an impact that he is stood there with no clothes on."
The scene was filmed in Slovakia and Claes' co-star Dolly Wells felt "guilty" as she was wearing multiple layers.
She said: "I felt quite guilty because I had so many clothes on."
The Danish actor, 52, admitted that he was initially reluctant to take on the role, because there had been so many iconic portrayals of Dracula in the past.
Claes explained: "When my agent called, I said 'Are you sure about that? Does the world really need another Dracula because there are so many good ones out there?' "
However, he was persuaded to join the cast after reading Steven Moffat and Mark's script.
He said: "When I read the script, I thought 'sure'. It's such a brilliant new take on Dracula.
"The new dynamic persuaded me to do it, as I didn't want to do something that's already been done."
Steven, who has worked on 'Doctor Who' and 'Sherlock', revealed that they specifically targeted a non-English actor and were persuaded to hire Claes after watching him in 'The Square'.
The 58-year-old star said: "We wanted someone tall, dark, handsome and specifically not English, which is a very tall order.
"I noticed Claes because he had a funny name, he's the second one (after Benedict Cumberbatch in 'Sherlock').
"We saw some clips from 'The Square' and immediately thought he was Dracula. That was kind of it, we didn't audition anyone else."
Mark also revealed that the idea for 'Dracula' came about after he had been working on 'Sherlock'.
He said: "It started as a joke, we had been shooting 'Sherlock' series three.
"I had taken a picture of Benedict with his collar up in silhouette against Mrs. Hudson's doorway. I thought it looked like Dracula and that was the seed of it."
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