I’ve always had a sight problem with actors who “act” — i.e., performers who are clearly using acquired skills to inject varying degrees of feeling into a given scene. The rule of thumb is that a performance that is driven by “acting” is very admirable and enjoyable, but not necessarily one you can believe in 100% because you’re too aware of the gears moving and various tricks and devices being applied.

(l.) Jesse Eisenberg in The Social Network; (r.) Colin Firth in The King’s Speech.

As good as Colin Firth‘s King George performance is in The King’s Speech, and without disputing the conventional wisdom that he’s probably going to win the 2010 Best Actor Oscar, I sense “acting” going on in his performance. Not to any problematical degree, mind — he’s inhabiting a member of the British royal family in a late 1930s mode, and there are only a few ways to skin a cat in this respect. By any measure it’s a quietly penetrating and fitting portrayal.

But I still felt less “acting” from Firth when he played a dignified gay college professor contemplating committing suicide in A Single Man. I detected very few gears and devices in that performance (Tom Ford‘s muted high-fashion directing style seemed to filter Firth’s emoting), and yet, as noted, they slip through here and there in The King’s Speech. And yet it’s a touchingly written character and Firth knows exactly how to play him, so it works overall. So I’m really not putting it down.

And yet the almost mystifying absence of noticable “acting” in Jesse Eisenberg‘s performance (if you want to call it that) as Mark Zuckerberg in The Social Network is, for me, spellbinding. He’s playing one of the smartest guys who ever sat in any room in any realm, certainly in internet visionary terms, and not once does Eisenberg indicate to the audience that he’s even slightly interested in showing that he’s got a hidden-soft-underbelly thing going on. He’s just that fucking guy, and he doesn’t back off for an instant. The notion that he’s performing doesn’t surface. At all.

And yet — this is the astonishing part — you can feel the guy he could be (and wouldn’t mind being if it didn’t get in the way of his Facebook dreams) and perhaps one day will be if he ever gets some therapy and really works through his issues. I’m delighted by the fact that Eisenberg/Zuckerberg’s emotional currents never break through, blocked as they are by his massive ego and intellect and hunger for power and affection from Rooney Mara‘s character (i.e., the girl who breaks up with him in the opening scene). And yet you can feel them trying to be heard in each and every scene. They leak through like tiny droplets of moisture (which in reality would be nitroglycerine but let’s not get technical) seeping out of a stick of dynamite.

Here’s a portion of Mark Harris‘s New York interview with David Fincher that discusses Eisenberg:

Harris: It was kind of shocking to hear Jesse Eisenberg doing Aaron Sorkin’s dialogue, because you suddenly realize this is what he was born to do.

Fincher: We looked and looked and looked. We read every young actor in Hollywood. And it had been rumored on blogs and stuff that we were talking to Jesse Eisenberg. And you know, I hate to be told what to do by blogs, so I was like, “Yeah, we should probably see him but I don’t know if this is his thing … ” And he put himself on tape reading the first scene, and I remember getting this thing on my computer and opening this little QuickTime, and here’s this kid doing Sorkin: the first person that we’d heard who could do Sorkin better than Sorkin.

“Oftentimes, you’ll say to an actor that, you know, the notion of being present is not to be thinking of the next thing you’re going to say but to actually be listening. You know, a lot of people are trained to give you the ‘thoughtful’ thing, but at the same time, they’re trying to process their next line. And Jesse can be half a page ahead, and in the now. I remember turning to Aaron and saying, ‘Okay, have we ever seen anything this good?’ He just said, ‘That’s the guy.’ We brought him out to LA and he came into my office and I said, ‘Hey, it’s a pleasure to meet you.’ And he said, ‘Great, what do you want me to read? I’ve prepared three scenes.’ And I said, ‘No, no, no. You got the job. We’re just having you here because we wanted to meet you and say hello, but you’re in the movie.'”