Toby Jones will be playing the most menacing villain in Sherlock history, according to the show's creators.

Jones, a British acting legend, was cast as the villainous Culverton Smith for season 4 of Sherlock. In a show that has featured many villains, including the devilish Moriarty (Andrew Scott), showrunners Steven Moffat and Mark Gatiss think Jones' character might be even worse.

"He's completely different [to the villains that have come before]. It's a completely different character. He's the darkest villain we've had," Moffat revealed in a new interview with Collider. "There was always something charming and engaging about Moriarty. There was something fascinating and actually amoral, rather than immoral, about Charles Augustus Magnussen [Lars Mikkelsen]. This guy is the purest evil. Sherlock [Benedict Cumberbatch] is actually appalled by him. He's the most evil villain we've had. I don't think that when you see it, you will disagree. He's horrific."

Gatiss elaborated on developing the Culverton Smith character as the most dastardly in the show's history.

"It's an interesting thing to chart. We made our Moriarty very different to [Sir Arthur Conan] Doyle's," Gatiss explained. "He's Irish, and he brings all his charm, his twinkle and his humor to it while he's also terrifying. Magnussen was a very blank, chilling business man. He doesn't see what he's doing as evil. Toby is doing something very interesting. [He's] an avuncular, funny seeming man with terrible teeth. We've given him terrible teeth, which are symbolic of the rot inside him. It's a great complex, shaded character. You're not quite sure what the relationship is with him."

If you're already intrigued by this villain, Culverton Smith is introduced in Doyle's short story, The Adventure of the Dying Detective.

Meanwhile, the fourth season of Sherlock is expected to premiere in 2017, though a specific premiere date has not yet been announced. The series typically returns in January, though it's not clear if this pattern will continue.