“Shallow,” the Bradley Cooper-Lady Gaga duet from the forthcoming remake of A Star Is Born, opens with an acoustic guitar that recalls strumming from the Peak Power Ballad Era — think the percussive nature of “More Than Words” and the filigrees of “I Remember You,” with a bit of “To Be With You” shagginess thrown in for good measure; Cooper’s slightly raspy voice brings to mind today’s country-pop singers in Unplugged mode. But when Lady Gaga — playing Ally, the ingenue who gets drawn in by Cooper’s grizzled rocker — comes in to cheers, “Shallow” explodes into colors, turning a simple love song into high drama.
Rock Powerhouse Gaga is one of her best personas, allowing her to channel her theater-kid background and pop-star present simultaneously; “Shallow” lets her not just revel but sound like she’s bathing in it, from the ovation accompanying her arrival to her final repetition of the chorus. The key moment, of course, is Gaga’s 17-second run at the song’s bridge, a vocal triumph that future generations will study. The musicians crouch into their starting blocks at 2:25, and two seconds later, she fires the starter’s pistol, teasing what’s to come with a breathy gasp; her voice then opens, and opens more, until she’s seemingly threatening to swallow the entire stage whole, sustaining its triumphant ending note before crashing back into its Bic lighter-worthy chorus. (Cooper’s somewhere in there, too, but Gaga steals the show as easily in Hollywood as she does in pop.)