Lars Mikkelsen on playing "supreme" Sherlock villain Charles Augustus Magnussen

And the man who plays him, 49-year-old Danish actor Lars Mikkelsen, has been talking to the BBC about what we can expect from his "supreme" super-villain.

"He’s described in the original novels as an opponent that Sherlock really hates," says Mikkelsen. "He loathes him, and he is based on a character that was real in the time of Conan Doyle. In Doyle’s novel he was an art dealer who lives on preying on other people."

Similarly to Moriarty, Magnussen is obsessed with Sherlock reveals Mikkelsen: "[He] is more or less infatuated with Sherlock." But he's a different kind of villain to Sherlock's former rival...

"Whereas Moriarty is playful as a villain, this character is more supreme," says Mikkelsen. "He doesn’t even need to raise his voice to dominate people. He doesn’t enjoy being a villain; I don’t even think he reckons himself as a villain, he just lives off preying on other people. He calls himself a businessman and it’s just a way of life for him."

Intrigued? Remember to tune into the Sherlock finale, tonight at 8:30pm on BBC1.

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