Justin Timberlake performs barbershop version of 'SexyBack'

By Meredith Blake

March 13, 2013 12 AM PT

Justin Timberlake’s unofficial takeover of NBC continued Tuesday on “Late Night with Jimmy Fallon,” where he’s camped out all week long following his fifth “SNL” hosting gig on Saturday.

On the second night of “Justin Timberweek,” the singer performed a new song, “Mirrors,” from his upcoming album, but it was his unusual rendition of “SexyBack” that was the standout moment of the episode.

At the suggestion of a viewer, Timberlake teamed up with “The Ragtime Gals” -- “Late Night’s” in-house barbershop quartet, known for their covers of raunchy songs like “It Wasn’t Me” -- on a new version of the infectious 2006 hit single.

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Somehow, the song’s PG-13 lyrics (“Dirty babe/You see these shackles baby I’m your slave/I’ll let you whip me if I misbehave”) sound even racier in a cappella, five-part harmony.

It’s the latest destined-to-go-viral collaboration between the musically oriented comedian and the comedically oriented musician, whose series of “History of Rap” videos have been a massive hit online. (We’re crossing our fingers that another installment will land sometime this week.)

While Timberlake is already reaching Beyonce-like levels of media saturation just days into a promotional press blitz, the singer’s weeklong residency has delivered “SNL” its highest ratings in more than a year.

Hey, NBC: You might want to put this Timberlake fella on retainer.

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