"I've dealt with murderers, psychopaths. None of them can turn my stomach like Charles Augustus Magnussen."
Sherlock Holmes meets his most heinous foe yet on PBS' Sherlock finale Sunday (check local listings for times). "Charles Augustus Magnussen is the one villain that Sherlock Holmes truly hates," executive producer Sue Vertue tells TVGuide.com. "He never hated Moriarty actually. They sort of admired each other. They have the same kind of brains. Whereas Magnussen is just calculated. He really hates Magnussen."
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Sherlock's loathing may not make the most sense initially. The late Jim Moriarty (Andrew Scott) was set up to be Sherlock's (Benedict Cumberbatch) ultimate nemesis, the flipside to his mad genius. Moriarty didn't seek out victims through any sadistic pleasure, but rather the victims were collateral damage in his grand schemes to provoke Sherlock. Unlike Moriarty, Magnussen (Lars Mikkelsen) "preys on the weak. He's a blackmailer," Vertue says. "He's just not nice. Moriarty was mad, but not cruel in a way."
Magnussen is described as having "dead eyes" and is based upon Charles Augustus Milverton, a character in the original Sherlock Holmes canon by Sir Arthur Conan Doyle who in turn was inspired by the real-life alleged blackmailer Charles Augustus Howell. Sherlock's version of the scoundrel thrills in finding people's "pressure points" -- people, issues or secrets they care about passionately -- and then exploits them.
Finding someone to play the worthy opponent to Sherlock was the next challenge. The producers only knew that they wanted a foreigner, someone not British. A few older American actors were considered, but it wasn't until Danish actor Lars Mikkelsen was scouting for parts in England did they find their Magnussen. "He's chilling. It's just the stillness that he plays that I think is brilliant," Vertue says.
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Fans of another TV villain should recognize the surname Mikkelsen. Lars is the older brother of actor Mads Mikkelsen, who portrays Dr. Hannibal Lecter on NBC's serial killer drama Hannibal. "I think Mads Mikkelsen's carving out of a different version of Hannibal Lecter is amazing, and his brother is equally, but very differently terrifying [as Magnussen]," series co-creator Steven Moffat, who also acts as the showrunner onDoctor Who, says. "Not at all terrifying in real life. He's the loveliest man with a south London accent. His English is phenomenally good, but he speaks with a south London accent, a bit Cockney. We had to tell him, 'No, you have to do it in a Danish accent.' So he had to go work on his Danish accent."
Mikkelsen's Danish background also required one additional adjustment. "I had to go onto Danish surnames and work out what sort of goes with 'Milverton,'" Moffat reveals. "I couldn't use 'Mikkelsen,' which would have been great. But I couldn't because that's his real name."
Check out a trailer for "His Last Vow" below: