If you heard laughter coming from your neighbor's house last night, odds are they had their tv tunes to "saturday night live." They had people more famous than ron claiborne. Hard to believe. Justin... See More
If you heard laughter coming from your neighbor's house last night, odds are they had their tv tunes to "saturday night live." They had people more famous than ron claiborne. Hard to believe. Justin timberlake, and jimmy fallon starring in some hilarious skits. We have been talking about this all morning. Abc's sara haines is here with more. Reporter: When this duo teams up, they don't disappoint and last night was no exception. Justin timberlake. Jimmy fallon. A dynamic duo. Totally live. That's the way we laugh it up. Reporter: The surprises continued throughout the night with special guests paul McCARTNEY NOTE HAVE YOURSELF A Merry little christmas ♪ ♪ let your heart be live ♪ Reporter: Madonna. Human nature. Republicans. Democrats. Why can't people get along? I'm glad you asked that barry. Reporter: Mayor bloomberg. Even the real barry gibbs. ♪ Reporter: Fallon's turn as the not so real harry styles. ♪ Reporter: While justin nailed his impersonation of fallon. It's so good. So great, my man. So dead-on jimmy couldn't handle himself. Reporter: While saturday's j.T. Was just the musical guest. As host of -- "saturday night." It's my in the box. Reporter: Going move for move with beyonce. ♪ I have to say, my favorite moment was when justin did jimmy, the whole time through the sketch, you see him going like this, yous quivering. That beyonce skit is ridiculous funny. It's amazing. Lot of talent there. Thank you, sarah. Coming up here on "good morning america" -- much more
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