Man and Boy: Dada, Almeida Theatre, London

Nyman is just the ticket

Michael Nyman's music is nothing if not useful - commissioned to play at the launches of cars and trains or pumping out of orchestra pits - but in Peter Greenaway's films it reaches an apotheosis. Watch a silent clip from The Draughtsman's Contract and you can almost hear the hysterically prancing soundtrack: ditto with Drowning by Numbers, A Zed and Two Noughts, and the director's other celluloid games of stylised obsession.

As a student Nyman immersed himself in American minimalism and Romanian folk music, and the resultant brew was in its modest way unique. Gradually, through orchestral suites based on film scores, this brew found its way into the concert hall. It also fuelled Nyman's shots at opera, but not even the best-known of those - The Man Who Mistook His Wife for a Hat - really passes muster. It lacks dramatic momentum, and treats the human voice as just another instrument. So what sort of risk was Almeida Opera taking by commissioning yet another shot by this irrepressible musical journeyman?

The idea was auspicious, and serendipity played a part. Growing up in the Forties, Nyman had been an avid collector of bus tickets, cigarette cards, and matchbox labels - as a member of the same generation, I can vouch for the fact that these were common obsessions - and when he discovered that the co-founder of Dadaism, Kurt Schwitters, had collected the same types of bus tickets, he conceived the idea of building a work round this congruence. Then the phone rang: his friend, the playwright Michael Hastings, another juvenile bus-ticket-collector, was contemplating writing a radio play about a young boy in London collecting tickets after the war. An opera was born.

But Schwitters was much more than a mere anorak. Painter, poet, performance artist, practical joker, and distant precursor of many a present-day Turner prize faddist, he had been forced to flee Nazi Germany and ended his days a sad refugee, still creating his monumental follies in a Lake District barn.

The "man and boy" in the title would have a double meaning: the work would turn on the relationship between a deracinated German and a London lad who shared a bus-ticket obsession, but it would also denote the fact that the old German was in many ways still a boy at heart. Imbued with the idea that the marshalling of ephemera might heal symbolic wounds, the opera would have a sweetly symmetrical underpinning.

From the moment the Almeida Ensemble started tuning, you knew Nyman hadn't changed his spots: here were the hurrying pulsations and chugging ostinatos on woodwind and strings which are his trademark. The concrete cubes which covered the stage, plus the computer-generated back-projections, indicated the hi-tech post-modern chic we have come to expect. And when the man, the boy, and his mother appeared as though on a double-decker bus, while Schwitters-style collages of tickets, buses, and bus routes appeared as a backdrop, everything seemed in place.

Hastings's unfussy libretto, with its graceful alternations of comedy and pathos, came across beautifully in this intimate space - at first one was more aware of it than the music, which felt like more of the same. But then one realised it wasn't: after some patches of Sondheim, the vocal style settled into Britten mode; Nyman had moved on. Each short scene got a different colouring, but the singers actually got arias, if of a strained and high-pitched variety.

And as the boy and the German made friends, and the mother and the German made peace (though not love), an engaging spell was cast.

No praise can be too high for young William Sheldon as the boy and Vivian Tierney as his mother, while John Graham-Hall's incarnation of Schwitters was a heroic piece of virtuosity. This heartfelt work rose far above pastiche.