Liza's Back! Royal Albert Hall, London

Anyone naive enough to believe the official description of this event – a "concert" – would have been disappointed, but the faithful at the opening of Liza's Back! knew better. Graham Norton, who introduced Liza Minnelli, called it much more accurately in his least offensive gag "a sequin-covered version of the Easter story".

Minnelli does not have much of a voice anymore, and her programme and patter (girlish confidences of boozing, pill-popping and marital happiness) made the heart sink for more than musical reasons. When one of her dancers exclaimed: "Would you believe it – she's over 50!" one found it hard, indeed, to believe anyone could reach that age having learned so little about taste, charm, and integrity. (Of course, what we see could be the canny construction of a woman skilled in marketing, who may be going over her act this morning, thinking it could use a bit more pathos here, a tad more nervous confusion there.)

Minnelli, however, has the most important attribute for a star, the one that trumps talent, staying power, and charisma every time: fans. Not only did they fill the house, they carried on as if they were at a real revival meeting, rising to their feet a dozen times with loud hallelujahs. When Minnelli, supported on both sides by dancers (an aid Dora Bryan has never needed), lifted her legs, they screamed. When she drank a glass of water, they roared. And when she emerged in a tiny black costume stretched to danger point, a roll of flesh lapping over the top, and asked: "Does this look all right?" they said yes.

During the first half, Minnelli showed almost no vocal range or power, talking or chanting her numbers rather than singing, and substituting pantomime for expressiveness. In "Something Wonderful," the line "He'll always need your love / And so he'll GET your love" was accompanied by a raised, shaking fist and a snarl to emphasise this alarming prospect. She paused before notes that had to be reached for or extended, and chopped up phrases or sharply dropped the volume in the middle of them – affectations that served her vocal inadequacies rather than the lyrics. After the interval, it became clear that Minnelli had been saving herself for her big numbers, "New York, New York," three songs from Cabaret, and those classics of pushy vulnerability, "Maybe This Time" and "What Did I Have That I Don't Have Now?" But the colour of the voice was imitation brass, the delivery routine. For all her self-protectiveness, Minnelli exposed her limits in her closing song, an a cappella rendition of "I'll Be Seeing You" that was breathy and uncontrolled. With this, Minnelli said, she was sharing our sadness at the death of the Queen Mother, a feeling that might have been better respected by changing the line in "Cabaret", startling in the circumstances, "When I saw her laid out like a queen".

A laid-back band whose most prominent instrument is a synthesizer and dancers who wave hats, TV-variety-show style, or engage in a sub-Fosse group grope complete the spectacle. An unbeliever feels out of place indeed at this orgy of American shamelessness and English masochism.

4, 6 & 7 April (020-7589 8212)