During host Jesse Eisenberg's monologue on tonight's Saturday Night Live, the Social Network star was surprised on stage by Andy Samberg-as-Mark Zuckerberg. But that wasn't all—shortly thereafter, the *real* Mark Zuckerberg showed up... and it was incredibly awkward!

[There was a video here]

Update: Here's a high quality version, courtesy NBC.com (Thanks, Chris!):

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