It's a magical opening, literally, executed with professional sleight of hand by baritone Geoffrey Dolton (with a little unseen help from the Magic Circle's Paul Kieve, the invisible man behind The Invisible Man). It's also a neat trick to lure our two volunteers, Sam and Susan Cooper, into taking a bit of overdue marital guidance, for that's exactly what Alan Jay Lerner's book has to offer as it proceeds to chart the breakdown of their relationship under the stresses and strains of 150 years of American "progress".
By following our time-travelling, age-defying duo in 30-year leaps from the simple rural idyll of 1790s Connecticut through industrial and technological revolution, female emancipation, prohibition, recession and depression, to the modern urban nightmare of mid-20th century emotional alienation - while a varied troupe of "vaudevillians" offers a stream of cynical asides - Lerner's fanciful format gave Weill plenty of scope to show off his acquired mastery of American popular styles, from ballad to torch song, square dance to foxtrot, soft-shoe shuffle to big, brassy blues.
But despite Caroline Gawn's sassy staging (a shade too "school of Richard Jones", perhaps), Wyn Davies's swinging beat, some fine solo singing (from Margaret Preece's Susan, in particular, equally convincing whether strutting her stuff in the suffragette striptease of the "Women's Club Blues" or searching her soul in the self-analysis of "Is It Him or Is It Me?") and an impressive display of mass tap-dancing by the chorus in the climactic "Divorce Ballet", the reasons for the work's long neglect are painfully clear: the uneasy jump cuts from time-zone to time-zone, the way that too many scenes are carried by dialogue alone - above all, the fact that Weill's tunes simply aren't good enough.
Take "I Remember It Well", the "our tune" of Sam and Susan's marriage. You might think that any show with a number like that just can't go wrong. The trouble is, it's the wrong tune: the one we all remember is from Gigi - same words (shamelessly recycled by Lerner), catchier music (Frederick Loewe), rendered truly unforgettable by Maurice Chevalier and Hermione Gingold. Like Sam and Susan, last seen tentatively tightrope-walking towards one another across the abyss, Kurt Weill never quite got it together again after fleeing Berlin for Broadway. After all, how many careers, or couples, can survive being cut in half and left dangling in mid-air?
n 'Love Life' is in rep at the Grand Theatre, Leeds, until Saturday (booking: 0113 245 9351), then on tour to Hull, Sunderland, Nottingham and Manchester
MARK PAPPENHEIMReuse content