PETER Egan and Phil Franks first forged their detective-and-doctor double act as Holmes and Watson in The Hound Of The Baskervilles four years ago.

Now they reunite under the direction of Robin Herford once more, this time in a production with a more intense focus, not so much a single story of Holmes in action on the moor, but more a chronological study of the inner workings of his oft-troubled mind from the moment that he and army doctor Watson first met.

Further intensity is lent by the format of the play: a two-hander, rather than Baskervilles’ two leads and a supporting cast.

Originally written as a West End stage vehicle for Jeremy Brett 20 years ago by Jeremy Paul on the back of their mutual success with their television series, it is a character-led psychological drama rather than a story-driven adventure.

Therefore it requires the heightened concentration that makes the scrunching of bags of sweets in the audience even more unwelcome than usual.

Especially so, as Herford and his production team of designer Simon Higlett, lighting designer Matthew Eagland and sound designer Matthew Bugg have taken such care to create a claustrophobic atmosphere in Holmes’s book-laden Baker Street lodgings, the stage on occasion being shrouded in almost as much mist as would be found on Bodmin Moor. Herford is a pastmaster at such creepy theatre, having directed The Woman In Black, but there are fewer spooky set-pieces here, save for Holmes’s showdown with his nemesis, Professor Moriarty, at Reichenbach Falls.

The turmoil that unfolds is largely in the head of Egan’s Holmes, under the influence of opium and cocaine for stimulation when no case consumes him, as he turns his powers of deduction upon himself.

When secrets and betrayal come to the fore, both Franks’s ever-loyal Watson and the audience are put through the grinder, as humour makes way for a dark journey to Holmes’s abyss.

Over its 90-minute span (including an interval), the play elicits quiet, inner pleasures, predominantly in the interplay of the trusty partnership of Egan and Franks, who relish the wit, intelligence and rhythms of Paul’s writing.

Yet you may wish for a little more drama, a bigger climax, something to set the pulse racing, rather than the measured, heavily detailed, immaculate storytelling.

* The Secret Of Sherlock Holmes, York Theatre Royal, until Saturday.

Box office: 01904 623568.