MANSFIELD, Mass. — “It’s the 21st century,” Radiohead singer Thom Yorke sang during “Bodysnatchers” last night at the Comcast Center, and even though we presumably all knew it, he and the band went out and proved it.

Remember those old movies from the ’60s about what the world would be like in the year 2000? Remember how there was always a scene where a band was playing, giving a musical hint as to what a brave, weird world the characters had landed in? Radiohead basically sounds like that. You’d be tempted to call them futuristic except that, y’know, they’re already here.

Over the course of the show the band played all of their latest album, last year’s In Rainbows, giving the crowd a heady mix of electronic beats and acoustic drums; rock guitars and unnerving electro keyboards; chilly, foreboding moods and lush baths of drone, all led by the heavenly voice of Yorke, who when he launches into falsetto sounds like he belongs to no ethnic group or gender — and whose often inscrutable lyrics add another layer to the Radiohead enigma. The stage set helped the effect, with tubes of light hanging down from the rafters and adding by turns harsh digital blips of light and an eerie, shadowless glow.

“Nude” and “All I Need” were comfortingly (though the lyrics “I am an animal trapped in your hot car” belied the musical mood), while “Bodysnatchers” and “Jigsaw Falling Into Place” were frantic. “Weird Fish/Arpeggi” was sleek and quick, and even the acoustic “Faust Arp” kept a chilly “futuristic” resolve. The odd time of “15 Step” flowed naturally enough to see Yorke do as much dancing as he ever manages. They mixed in older songs such as “There There” — with guitarists Jonny Greenwood and Ed O’Brien banging on drums for most of the Bauhaus-inspired song until drummer Phil Selway kicked it into high gear and Greenwood tore off his first solo of the evening — and the ’60s rock-inspired anthem “The Bends,” as well as “Kid A,” with its chiming keys and bass chords. “The National Anthem” was as close as they got to a typical riff-rocker in the early going, and “Exit Music (For a Film)” revealed a Pink Floyd influence that otherwise is overrated.

The mix of old and new was perfect during “Everything In Its Right Place,” in which Greenwood and O’Brien manipulated a repeating echo of Yorke’s vocal until it took on the quality of an instrument on its own, and they did the same trick, adding Selway’s drums to the mix, in “The Gloaming (Softly Open Our Mouths in the Cold).”

The half-hour of encores was devoted to older riff rockers (after a twisted Radiohead fashion, of course), such as “I Might Be Wrong,” “Paranoid Android” and “Wolf at the Door.” They ran the gamut to wrap things up, with the piano ballad “Cymbal Rush” (from Yorke’s solo album The Eraser), the somber “Karma Police” and the stunning “Idioteque,” with nothing but vocals, drums, drum machines and electro squiggles.

Grizzly Bear opened the show with long, slow, limpid songs with simple structures and occasionally lovely vocals but not much in the way of instrumental technique. There were occasional hook-laden moments, such as the recorder intro on “Fix It,” and drummer Christopher Bear came into his own on the last two songs, “On a Neck, On a Spit” and “While You Wait For the Others.” But too many songs stayed stuck in first gear.

rmassimo@projo.com