If there's one thing you have to do in adapting Nathaniel Hawthorne's novel The Scarlet Letter, it's to retain and amplify the sense the characters are living in a stiflingly repressed society, ruled over by the 17th-Century equivalent of the Taliban.

Set among the Puritan folk of colonial Boston, the story is of Hester Prynne, a woman who bears a child out of wedlock and steadfastly refuses to reveal the identity of the father - even though it could save her the ignominy of having henceforth to walk abroad with a large red "A" (for "Adulteress") pinned to her dress.

However, from the opening scene of Phyllis Nagy's Chichester adaptation, wherein Hester is forced to exhibit her "A" for the first time, there's a sense that neither she nor anyone else sees it as that big a deal.

Over the next couple of hours there's a certain amount of interest in the continuing question of "Who's the daddy?" (it's the vicar, as it happens) but, considering it's one of the main plot strands, it's surprising how mild-mannered that interest is.

Some good acting goes a small way towards compensating for the absence of dramatic tension.

Sure, there's a lack of spark (repressed or otherwise) between the leads but that's almost to be expected. In any case, Elizabeth McGovern is an engaging Hester, and Jo Stone-Fewings does a fine job of portraying the conflicting impulses which lead Hester's past and future lover, the Rev Arthur Dimmesdale, to mental disintegration.

Katherine Tozer is suitably pestilential as the child, Pearl, and Alan Williams is compelling as Roger Chillingworth, the quack doctor who poses as Dimmesdale's friend but is actually Hester's vengeance-seeking husband.

If there's any sense of danger to be had, it derives from the aptly named Chillingworth rather than from Martin Duncan's ineffectual Governor Bellingham.

The actors work hard on our behalf but ultimately they're making bricks without straw. How much of the blame for this should be apportioned to Phyllis Nagy the dramatist and how much to Phyllis Nagy the director, it's impossible to say.

Running until September 8.