After the amicable exit of Rostam Batmanglij, Vampire Weekend’s co-founding in-house producer, co-writer and multi-instrumentalist, an awkward transitional period felt inevitable. But instead of shrinking the band’s universe, frontman Ezra Koenig expanded it tenfold—working with writers and producers throughout mainstream pop-rock (Mark Ronson, Danielle Haim), hip-hop (DJ Dahi) and indie-soul (The Internet guitarist Steve Lacy), building up a sprawling sample catalog and pushing Vampire Weekend past indie-rock into a more fluid headspace untethered to genre. The result is a complete rebirth: Their ambitious fourth LP, Father of the Bride , with its gleeful stylistic shifts and open-door collaborative policy, slam-dunks the traditional four-piece rock band format into the metaphorical dumpster. Koenig eases you in slowly with “Hold You Now”: a gently fingerpicked acoustic guitar figure and familiar folk-rock melody, accentuated by a divine choral sample from a Hans Zimmer score. But from there, things get gloriously unpredictable: The melancholy “My Mistake” ventures into ornate piano and jazzy saxophone; “How Long?” pairs a swaggering hip-hop beat with wobbly synths and a signature Koenig hook; “This Life” veers into rockabilly; digital lullaby “2021” centers on a twinkling synth sample; several cuts, including the proggy guitar groover “Sunflower,” mine the unexpected influence of the Grateful Dead. But this isn’t showboating. Father of the Bride , like all Vampire Weekend, is rooted in charming marriages of melody and lyric—it feels like them, even when it doesn’t. “It’s what you thought that you wanted/ It’s still a surprise,” Koenig sings, appropriately, on the dreamy “Unbearably White.” Truly the best of both worlds.