As Burt Bacharach's spellbinding 18-song medley of his finest moments reaches a halfway mark, it's hard not to feel sorry for the relative upstart tunesmith, Elvis. Sure, Costello has his share of 24-carat classics littering a two-decade career, but whose achievements wouldn't be dwarfed in face of the sheer volume and genius of the Bacharach canon?
One imagines that, having left the stage to allow Burt to charge through a seemingly endless parade of million-sellers, Elvis must be quaking in the wings, as "What's New Pussycat?" is followed by "Wives And Lovers", giving way to "Alfie", "A House Is Not A Home", "Walk On By" and "I Say A Little Prayer". What the hell was coming next? A stage-hand bellowing "Taxi for Mr Costello!" would have been the most welcome sound to his ears.
But, then something unexpected and genuinely magical happens. Costello saunters back on stage, Bacharach fires the 28-piece orchestra with the intro to "Make It Easy On Yourself", and — no word of a lie — Elvis delivers one of the most spectacular vocal performances of his life. The first shaky 20 minutes of tonight's marathon set (passable but unremarkable readings of "Tears At The Birthday Party" from the duo's Painted From Memory album, a faltering "I Just Don't Know What To Do With Myself") are forgotten, and the concert switches from a mere curiosity value confrontation to a full-blown event.
It's as if Costello needed a reminder as to why he's here, a kick-start to shake him out of his forelock-tugging in the presence of an Old master. Elvis has previously shared a stage with, among others, McCartney, Dylan, Bennett, Orbison and Springsteen, but arguably he's made the mistake of paying Bacharach too much respect. They share equal billing on the ticket stub, why not show the world what he can do when house lights go down?
There's an interesting visual contrast between the two men: Bacharach is the epitome of laid-back California showbiz in a pastel suit, like a white-haired Montalban in Fantasy Island, while a slightly portly Costello looks uncomfortable in a size-too-small tux, like Robert De Niro in the last reel of Raging Bull. Yet, curiously, the man and his menswear grow into each other, and, having found his footing and his voice, Elvis is soon clicking his fingers, and strolling back and forth across the stage with left hand in trouser pocket.
Comparisons with Sinatra's celebrated appearance at this very venue in 1970 are unavoidable, tonight's crooner apeing the laconic grace, if not the vocal power, of a performance he's patently seen on video at least once. Not that I'm about to argue that Elvis in any way possesses the formidable voice Frank did. but the fact that this once sneering New Waver isn't the best singer in the world actually works to his advantage. Think of Bacharach and you think of pitch-perfect vocalists like Dionne Warwick or Scott Walker, but it's the frailty and shortcomings of Costello's voice which, in many ways, is more suited to these fabulous songs of heartbreak and human weakness.
When Burt takes a break, allowing Elvis to revisit former glories (Steve Nieve taking over orchestra leading duties), we hear profoundly moving re-arrangements of "Accidents Will Happen" (slipping into a fitting coda of Bacharach's own "24 Hours From Tulsa") and "Alison", revealing both songs' original debt to the master of musical melodrama.
As Bacharach returns for the devastating closing triumvirate of "Anyone Who Had A Heart", "My Little Red Book" and the pair's first, awesome collaborative effort, "God Give Me Strength", the majestic logic of these two great songwriters working together shines like a beacon.
Earlier, many of us were thinking Elvis should have left the building, but as we wend our way home, hearts and heads full of truly affecting sounds, we're awfully glad he stayed.