MIST descends on desolate Dartmoor and a ghastly howl quickens the heart. In the darkness, something seems to rip through the backdrop; Charles Baskerville lies dead.

How scary, especially as the hound of the Baskervilles is but a sound in a marvellously melodramatic start that is spooky and beyond immediate explanation; the stuff of Conan Doyle.

Not for long, however, because The Hound will go barking mad in the dextrous hands of Peepolykus, instantly breaking theatre's fourth wall to introduce themselves and issue a health warning for anyone suffering from a heart condition, a nervous disorder, low self-esteem or a general inability to tell fact from fiction.

After ten years of original works of improvised lunacy and irreverence, these comic clowns have devised a show from a classic text for the first time, company founder John Nicholson working with writer Steven Canny on a script that veers off the straight and narrow as often as a Berwick Kaler pantomime plot.

In 2005, Ridiculusmus sallied forth in a two-handed The Importance Of Being Earnest, but that was already a comedy, and so Peepolykus is closer in spirit to Patrick Barlow's "touching up" of John Buchan's The 39 Steps from the same year. As with Barlow, Lip Service and North Country Theatre, Peepolykus make a drama out of a staff-shortage crisis, playing 20 roles between them, while shaking the dynamic of Holmes and Watson's relationship out of its comfort zone on stage and screen.

Sherlock Holmes has suddenly turned Spanish in the handsome form of Javier Marzan. His Manuel accent is so deliberately haphazard and close to impenetrable that the second half opens with the comic highpoint of a snapshot replay of earlier events in response to a mock audience letter of complaint. What's more, alongside the chameleon Jason Thorpe, Marzan must play a whole heap of other characters too; there's no time for Holmes's traditional recreational drug of choice, only the ubiquitous pipe.

Nicholson's Watson, meanwhile, is working under the illusion that he is in sole charge of the murder investigation, when the audience knows otherwise, and with his Stan Laurel startled hair and baffled air, he brings pathos to comedy that is otherwise amiably daft but prone to over-long diversions from the plot.

Orla O'Loughlin's production should have been scarier too; instead it has more bark than bite.

The Hound Of The Baskervilles, Peepolykus, West Yorkshire Playhouse, Leeds, until February 17. Box office: 0113 213 7700.