In Sherlock Holmes: A Game of Shadows, actor Jared Harris plays iconic villain Moriarty, with the perfect blend of menace and charm. He is the intellectual equal of the world’s most famous detective, Sherlock Holmes (Robert Downey, Jr.), but without a moral compass, allowing his capacity for evil to be endless.

During this exclusive interview at the film’s press junket, Jared Harris talked about how he ended up playing Moriarty, how daunting it is to play a genius criminal mastermind, the importance of keeping the character’s motives mysterious and unexplained, that he loves  a good fight scene, and how he’d love to revisit the role, if they ask him back for another film. He also talked about taking on the historical figure Ulysses S. Grant for Steven Spielberg’s Lincoln, working with Daniel Day Lewis, who stays in character throughout the shoot, currently filming the next season of Mad Men, and his return to Fringe. Check out what he had to say after the jump:

Question: How did you end up playing Moriarty?

JARED HARRIS: I was told that there were a couple of different versions that they might go about doing. I was considered as being part of one version of it, and they came to talk to me, to see if I would be interested in it, after they had approached my agent first. I have no idea how much of it is true because I’m not involved in those conversations and I have no idea who they really went to, but as I understand it, there was an interest in getting a film star. And then, for some reason, that didn’t work out. I was in Switzerland on a Friday, and they said, “If you can get to London by Saturday to meet Guy [Ritchie], they want to cast this part really quickly.” So, I flew there and met him, and then flew back to Los Angeles. I was offered the part by the time I had arrived.

Is it daunting to take on a role that’s supposed to be not only this mad genius, but also the biggest criminal mastermind to have ever lived?

HARRIS: Yes. Yes, it definitely was. But, when you actually get into it, in terms of the literary side of it, he’s only in two stories. My thought process about that was that I read what was in the stories and tried to get what I could out of them, in terms of anything that was going to be useful. The most important part about that character is the sense of his threat and the mystery that the character has, and really it was from the stories that he didn’t appear in. Actually, that’s more important. You have to deliver that part, rather then delivering the guy who actually appears in those stories. That’s been done. You can go on YouTube and see those versions of it. In a way, what happened with all of that was that it was more about deciding what not to do without being totally sure about what you were going to do. As you started to take away things, you started to be left with, “Well, this is what it is then.” Honestly, a huge part of the character was played by Robert [Downey]. When you’re doing a Shakespeare play and you have to play the king, one of the axioms of the theater is that you can’t play a king, people must treat you like one. The responsibility is for everybody else to achieve that element of the performance. The respect and the sense of danger and menace that Sherlock Holmes attributed to Moriarty was a huge part of it.

Was it important for you to keep his motives very mysterious and unexplained?

HARRIS: Yes, I think it works better. There were 15 pages of script for that first scene that we shot, and I think I said one line from those 15 pages. The rest of it was all made up, on the first day that we started shooting the sequence. The way I thought about preparing was that I looked at other movies with villains that I responded to and admired, and wondered, “What worked about that? Why did that work, and then this one didn’t work?” It dovetailed what I was thinking already, which was that, the more you’re left to fill in about the character, in terms of not knowing why he’s doing what he’s doing, the scarier he is. The Hannibal Lector thing, when you find out that he was captured by partisans and had to eat his sister, it’s so mundane. The explanation becomes banal and you drain all the mystery and the fear and the threat out of it. So, I didn’t want to do any of that. And, they were already on board for not doing the bad guy monologue. They didn’t want to do that. They realized that there were huge, giant pitfalls on either side of this, particularly after what Mike Myers has done with the Austin Powers films. It is really easy to find yourself in Dr. Evil territory, very quickly.

I’ve played quite a few villains, and you have to do them the way it’s been written, but I personally feel that people who are villains and who get away with high crimes, if they seemed like screaming maniacs, no one would trust them. These people are so successful because they are friendly and charming and personable, and they manipulate the fuck out of you. You don’t know it’s going on, and when you start to suspect they might be, you go, “Oh, no, they actually like me. They might do that to them, but they wouldn’t do that to me.” That’s how [Bernie] Madoff must have fucked all those people over. He has to be able to suck you in. If the devil roams the earth, he’s the most charming bastard on the planet. That’s how they get away with it.

What do you think it is about the characters of Holmes and Moriarity that allows them to have this symbiotic relationship?

HARRIS: In this, the idea is that they are intellectually equal to one another. I think they see that genius in one another. With Moriarity, I think he sees Holmes’ moral code as something that limits him. If he didn’t have it, he’d be able to achieve anything he wanted. There must be something about that, that would be curious to the other person. It’s, “What could I do, if I didn’t have that and I wasn’t bound by that?” There’s a fascination on either side.

Was it fun for you to get to do the fight scenes?

HARRIS: I love a bit of fisticuffs! The idea was that it would be a combination of styles. Robert [Downey] has his martial arts training and he has that very short, direct style of blocking and punches. Moriarty has more of a boxer’s approach. They tailored it towards our abilities. I used to box when I was younger, so I understand the weight distribution of doing all of that. It was great fun. I love doing all that stuff. I went to English drama schools, and you train in stage combat, sword fighting and physical combat. I love it. It’s the bit that reminds me of being a kid.

With Sherlock being as open-ended as it is, and talk of a third film already having started, would you want to revisit Moriarty?

HARRIS: I don’t think about that because I’m not involved in those conversations. If I started to think about it, then I would start to create a desire and a wish inside of me that I have no ability to affect the outcome of. I loved working with Guy. I loved working with Robert. I loved working with Lionel [Wigram] and Susan [Downey]. That atmosphere that they talk about, that isn’t just hype. That was what it felt like, being on set. Would I like to be in that environment again? Of course, I would. But, in terms of what they want to do with the story, I’m not part of that nucleus. It’s out of my hands, that bit.

How daunting is it to take on a historical figure like Ulysses S. Grant for Lincoln?

HARRIS: I like challenges. If you’re involved, as one is, in filmmaking, you want to challenge yourself. You don’t want to repeat what you’re done before. In terms of playing that character, I would love to do a whole series on that character. He’s fascinating. I absolutely love him! He’s a complete enigma. Within this, you have to just do what it is that Tony Kushner wants you to do. He’s constructed a story and there are requirements that he needs from each of the different characters. There are loads and loads of characters in the story, and you have a requirement, in terms of the function of the story. Having done it before, playing Warhol and John Lennon, I don’t feel like I played John Lennon or Andy Warhol. I feel like I played Mary Harron’s conception of Andy Warhol (in I Shot Andy Warhol), and the writer of The Two of Us, his version of John Lennon. You go off and do all this research, and you might find that your research is at odds with what the person has written. You either reconcile that with the writer, or you must accept that it’s not your version. If you want to do your version, go off and write it. You bring your knowledge to it, and you can use that to shape it and color it, but it’s someone else’s version of that character. You’re not actually playing the real person.

What’s it like to work with an actor like Daniel Day Lewis, who stays in character all the time?

HARRIS: The man is awesome. He’s awesome. I understand what that’s about and why that is. It takes a tremendous amount of concentration and focus. It’s quite easy to start to discover that you’ve drifted off of it, when you start chatting about the best place to get a steak in town, or the football game, or whatever. You do all this work to get yourself in the zone, and it’s not that long. You show up to work, you stay in the zone, you’re focused, and when you’re done, you go off. I’m sure he doesn’t speak to his children as Abraham Lincoln. It’s for the period of time that he’s at work, that he does that.

How is it to return to Mad Men and reprise that role again?

HARRIS: We’re shooting that right now. I was on set on Thursday. I love it. It’s great. Matt Weiner is an amazing writer. He’s one of the best, greatest writers that’s ever written for television, or just written. I know how lucky I am, having an opportunity to work on something like that show. The scripts that come in, you’re thrilled to read them, whether you’re in them or not.

Was it fun to also get to return to Fringe this season, with so many fans of the show wanting to see your character come back?

HARRIS: I love that show. I love the whole madness and conspiracy theory of it. It appeals to part of my character. The paranoid element that that show has, I love it.