Anna in the Tropics, Hampstead Theatre, London

A new lector is employed at Santiago and Ofelia's traditional Cuban-style cigar factory in Tampa, Florida, in Nilo Cruz's Pulitzer prize-winning play Anna in the Tropics. It is the late 1920s, and the lector is an important fixture in the industry: he reads to the (often illiterate) workers as they labour - from fiction, news, even political tracts that sing sedition to the ears of the bosses.

The socio-political importance of the figure, as not only entertainer but educator, is to be gleaned here only from a programme note. What is left behind on stage is Juan Julian, a swoon-worthy man in a white suit, who drives all the women wild (one fan wets herself at the mere sight of him) and all the men to surly inadequacy.

Julian (Enzo Cilenti, who has little to work with but becomes a winning presence) elects to read Anna Karenina - from an edition with a suitably lurid dustjacket. From there, it is inevitable that he should become Tolstoy's Vronsky and beat a path to the smouldering Anna figure of Conchita (an outstanding Rachael Stirling).

The factory becomes a sort of book group, with the women's imaginations and passions aroused by Tolstoy. Under his - and Julian's - influence, poetic lines begin to waft from even the most unlikely characters, but are too often left to hang in the air that we may admire them.

The director, Indhu Rubasingham, moves the busier scenes well - in the penultimate, party scene several vignettes are exposed deftly, with clarity and lightness of touch - but many scenes are ponderous. The whole is weighed down by an over-realistic approach, an approach that is itself further encumbered by the unfortunate decision to burden the English cast with Hispanic accents. If James Naughtie was agog at the stage Oirishness of By the Bog of Cats, who knows what he would have made of these stage Latinos?

Once the ear has tuned out the interference of the accents, Stirling's defiant Conchita commands every scene she is in. Diana Quick, as Ofelia, is a twinkly, sensual presence. And just as Peter Polycarpou's cartoon bumbler Cheche is beginning to grate, he succeeds in pulling back the mask to deliver a couple of nasty shocks, to great dramatic effect.

But where Tolstoy leads the reader through his epic story, making no judgement and calling for no blood, Cruz cannot resist editorialising, and these moments draw the play perilously close to the soap suds. A monologue on the death of hand-rolled cigars being emblematic of the passing of a gentler, better way of life blithely ignores the sweat-shop conditions and long hours of early mass production that kept the workers illiterate and in need of a lector in the first place.

I seem to remember one review of the original Broadway production of 2003 damning it with faint praise as "moderately fascinating". That pretty much covers it: close - but no cigar.

To 8 January (020-7722 9301)