Penny Dreadful

The language used in season 2 (Verbis Diabolo) is a fictional amalgam of Aramaic, Ancient Greek, Latin and an obscure Arabic dialect called (in phonetic English) "Kan Allah Musali-Algins". The language, Verbis Diabolo was created specifically for the show by the curator of the London Historical Societies Emeritus Professor of ancient languages.

The show is using many metaphors to point out the hidden or dual nature of the main characters. One of them is shooting scenes in reflective surfaces like mirrors. Most notably though is the dark versus light depiction of Vanessa and Mina.

As creator John Logan had never written a television series before, he did not produce a spec script, but instead wrote the first two episodes directly. When he had the opportunity to pitch it to Showtime, he also wrote a 40-page Bible exploring the characters and story, with the network eventually buying the show.