First Night: Evita, Adelphi Theatre, London

Oh, what a show! Little Mother brought to life by Argentinian actress

The cynic in me thought that it might even be a handicap having an authentically Argentinian performer playing Eva Peron in Michael Grandage's much-anticipated revival of Evita.

The commentator who claimed that Andrew Lloyd Webber's score is "about as Latin as steak-and-kidney pie" was wilfully overstating the case, but there is something more than a touch ersatz about its South American inflexions.

So it's a pleasure to report that the piece not only survives but thrives on the violent eruption of reality that comes in the diminutive shape of Elena Roger. As she charts the anti-heroine's progress from trashy opportunist to second wife (and First Lady) of the fascist Juan Peron and then to folk saint, Roger is simply sensational.

When this kid from the sticks hits the capital in the number "Buenos Aires", it's as a whirlwind of witty, drop-dead determination, every electrifying high-kick and tumbling, teasing phrase in that furious samba-extravaganza announcing the character's drive, devouring appetite, and sense of arrival. "Stand back!/You wanna know what you're gonna get in me?/Just a little touch of star quality..."

For "just a little touch", read "avalanche". Ms Roger has a wide, voracious mouth and a clarion voice capable of thrilling shrillness and of a pensive purity that's just on the point of curdling. She can also drop into a searing privacy that nonetheless feels partly calculated, as in her extraordinary, modulated reprise of "Don't Cry For Me..." when as a dying woman, she recycles her greatest hit in a renunciatory, damage-limiting broadcast.

Michael Grandage, one of our best directors, must have had to pinch himself to believe that Roger actually had dropped into his lap. His powerful production is full of acid humour, alert to the recklessness of a show that leaves itself open to the charge of glamourising fascism and of treating the well-heeled audience with a cynicism similar to that with which Eva and Juan Peron manipulated the shirtless masses.

Philip Quast, who is in excellent voice, makes a wonderfully uneasy President. For my taste, though, Matt Rawle is too straightforwardly likeable as the ironic commentator (and Eva's alter ego), Che Guevara. This character needs to be more abrasive and challenging to generate the requisite tension.

Does the piece train a critical eye on the decline of politics into showbiz, or does it merely cash in on this phenomenon? Grandage's production demon-strates that, if you could answer that question definitively, the musical would have failed as a revealing experience. It does not disqualify the piece or Ms Roger's extraordinary performance to say that the real-life Eva would probably have loved them.