A new interview with Tom, apparently from before the season 3 news was revealed, has been posted by Yahoo News. Read it in full on the site.

Riley said that last season the makers of Da Vinci's Demons had realised that the supernatural twists were something that viewers were reacting to and it was probably those that allowed them to accept the more anachronistic flourishes in the storylines. But he adds that some of the supernatural elements are built on fact.

"The sect of Mithras was completely real," he said. "They existed and the figures that we show, the lion-headed figure, the Mithiran, they were genuinely there. They are built into the catacombs below Rome.

"Who the followers of Mithras were and what they were has been lost in history but there are remnants of their poetry. Some of the strangest stuff in season one - all of that 'I am the son of earth and starry heaven', all of those things are lifted directly from Mithraism.

"Strangely enough, some of the stuff that people would assume is fantastical isn't and the other way round."

Riley has immersed himself in the history of the time, particularly researching Da Vinci's background, though he admits that the version of the artist in the show is "unusual". "I thought it was my duty to find out as much about him as I physically could," he said.

"I studied him as a man, I studied his work, his journals. There is a lot of belief that he was somewhere on the Asperger's syndrome spectrum and I spent a lot of time with Asperger's sufferers and tried to incorporate those traits into his character.