Steven Moffat and Mark Gatiss are working together again – but rule out doing Frankenstein

Directed by Gatiss and penned by Moffat, the story follows couple Peter and Debbie (played by Inside No 9's Reece Shearsmith and Sherlock's Amanda Abbington) who are horrified when an over-friendly woman (Frances Barber) whom they met on holiday arrives on their doorstep.

According to the play's synopsis, it will take "a hugely entertaining and satirical look at middle-class England's disastrous instinct always to appear nice."

Although definitely a welcome announcement, it may be a surprise for the fans theorising a Frankenstein adaptation was on the way from the duo.

Why did some expect this? Well, during the third and final episode of BBC One's Dracula, Gatiss's character Frank Renfield encounters a very enticing clue to his cryptic crossword: "Unscrupulous doctor deployed tanner's knife (12)"

It was thought that the answer to this – Frankenstein ('unscrupulous doctor' is the definition and 'tanner's knife' is an anagram of Frankenstein) – was a hint to the next monster series the duo would be adapting. Sure, if correct, it would be a very subtle clue. Yet you could argue that's just a hallmark of the pair's ingenious writing...

However, as Gatiss recently told RadioTimes.com there is a hidden story behind that crossword – but not a hint to an upcoming show. "That was just, well, I asked Steve Pemberton to do it. He wrote the whole crossword in his nom de plume as the Sphinx from Inside No 9."

He jokingly added: "Replete with references to Inside No 9, and still no part for me."

Although The Unfriend is the duo's next scheduled project, could Gatiss and Moffat reunite for another TV show? Very possibly.

Well, at least that what Moffat may have subtly hinted when speaking to us. When asked if he was planning another series with three 90-minute episodes, he responded: "I have no idea. It depends on what it is really.

"We did Dracula like that because Sherlock worked like that. We did Sherlock like that because that's how the BBC commissioned it. But there are all kinds of different ways of doing stuff, so I don't know. Time will tell!"

So, if Moffat is thinking of different TV formats, does that mean another TV show is actually on the way? And was that crossword secretly gifting fans an early clue about a Frankenstein series after all?

Answer: probably not. However, as Sherlock himself would tell you, you'll only stumble on the truth only once you've completely eliminated the impossible.

Additional reporting by Huw Fullerton

Dracula is streaming on BBC iPlayer in the UK and Netflix in the US