AGATHA Christie's 1953 courtroomdrama Witness For The Prosecution had never been performed in a site-specific production until York company Theatre Mill applied to Christie's estate.

The delighted estate approved the request and and should be even happier with Samuel Wood's engrossing, hugely enjoyable production in the packed Council Chambers of the York Guildhall.

You could not imagine a better setting to re-enact a court case: solemn, dark, wood panelled, with seating arranged as if in an amphitheatre that serves as a public gallery, with other members of the audience in the jury seats or near the judge.

Even before entering the chambers, the audience is pointed in the right direction by one policeman and had bags checked by another. Both turn out to be part of Wood's cast.

Likewise, once seated, everyone is addressed/dressed down by the Clerk of the Court (Paul Toy), who not only instructs that electronic devices should be switched off but also that we should all stand on the entry of the Judge, Mr Justice Wainwright (Ian Giles, whose enjoyment of the role is manifest).

Andrew Dowbiggin's Leonard Vole, a man of gentlemanly airs but washed up financially, stands accused of murdering the nice "old" woman (aged 56, it turns out), whom he had befriended to his ultimate financial benefit.

Where was he at 9.30pm on the night of her murder? At home with his mysterious German wife Romaine (the suitably haughty, unnerving Rachel Logan), as he claims, or at the house of the victim, as austere Scottish housekeeper Scot Janet Mackenzie (Pam Hilton) insists.

Topped up on tea by giddy, polka-dotty office girl Greta (Helen Buchanan), David Bowen's decisive, instinctive Sir Wilfrid Robarts QC must construct a defence for the slippery Vole in tandem with lawyer Mr Mayhew (Adam Elms, in a humorous second-fiddle turn once more, after his Dr Watson in Theatre Mill's autumn show).

Logan's Romaine is constantly intriguing in vintage Fifties mode, surprising both prosecution and defence with every utterance, and it is the battle between Bowen's assiduous QC and Clive Moore's smug, thin-nosed prosecution QC, Mr Myers, that makes Wood's production such a joy as the twists and turns outdo a grand-prix circuit.

Both performances, as the lawyers conduct a battle of will and wit, make you almost forget you are watching a play, as you become so caught up in the ebb and flow of the case. Christie's meticulous grasp of courtroom etiquette and matters of law add to the authenticty too, typified by Mr Justic Wainwright's gleeful quoting of case law.

And yet it is a play, of course it is, one that plays to the rules of the Queen of Crime with Christie's wonderful sense of rising drama and her relish for false leads and surprises.

Like last week's Black Coffee at the Grand Opera House, it is a far superior work to The Mousetrap, not least because of the playwright's smart humour, whether in the verbal clashes between Sir Wilfrid and Mr Myers or Tom Jackson's cameos as the outwitted Inspector Hearne and Mr Clegg.

Kill for a ticket.

Witness For The Prosecution, Theatre Mill, York Guildhall Council Chambers, until April 20. Box office: 01904 623568 or yorktheatreroyal.co.uk