Well, this is unexpected.

When Justin Timberlake announced this week that he had completed a new album, he did it with an over-the-top video that shows him running with horses and kneeling in a frozen field.

“It feels like mountains, trees, campfires,” we hear Timberlake’s wife, Jessica Biel, say about “Man of the Woods,” due Feb. 2, two days before the pop singer headlines the Super Bowl halftime show.

The idea appeared to be a deeply self-conscious return to roots — that after the polished digital textures of 2013’s “The 20/20 Experience” (whose cover had him wearing a tuxedo), Timberlake is taking up the down-home fundamentals of his native Tennessee.

Yet that’s not quite what happens in “Filthy,” the new album’s surprising lead single, which came out Thursday night along with a new video.

Produced by Timberlake and his old pals Timbaland and Danja, “Filthy” is a throbbing, proudly raunchy electro-funk track that has Timberlake begging somebody to put her dirty hands all over his body.

“What you gonna do with all that meat?” he asks, and making jerky to enjoy on a hike isn’t what he seems to have in mind.

Timberlake moves even further from the anticipated outdoorsy concept in the music video for “Filthy,” in which he plays a Steve Jobs-like tech maven who unveils a dancing robot at the Pan-Asian Deep Learning Conference (as a title card has it).

But perhaps our dude still has a country tune up his organic-flannel sleeve: On Twitter, Timberlake suggested that “Filthy” is the first of four songs he’ll release before “Man of the Woods” finally comes out.

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