It is a long time since I was back-stage at the Oxford Playhouse, but I hope there are four comfortable resting areas and copious supplies of something to relax four actors at the top of their game when the curtain goes down each night this week.

This theatrical version of the Hitchcock film of The 39 Steps (yes, the Buchan original is in there somewhere, but don't go expecting to find it too obviously) is the touring offshoot of a show that has occupied a theatre in the West End for a long time - and I refuse to believe that the London cast of four is a smidgen better than that of David Michaels, Clare Swinburne, Colin Mace and Alan Perrin, who provide a true stage tour-de-force.

There is not a spare moment, there is not a loose performance (among many roles, you understand) and I doubt if there is a bucket big enough to contain the sheer sweat that must drop off the three male artists during this hilarious, quick-change swinging success; I of course exclude Ms Swinburne - suave, sexy, man-eating anD coquettish as her roles variously call for - from this rather vulgar image.

Michaels is the only person to play one part throughout - Richard Hannay - and delivers one of those heroic stiff-upper-lip performances that are brilliantly all the better for not going completely over the top.

Messrs Mace and Perrin between them play about 15 other roles - Perrin quite brilliantly. His influences are clear: a bit of Stan Laurel in one part, a noticeable Julie Walters in another and an overwhelming Stanley Baxter in a third. There are practical delights throughout which raised sustained rounds of applause from the sold-out first night audience: with a minimum of props, for example, a train goes to Edinburgh, Hannay climbs over the Forth Bridge and, later, a bog (expertly presented by Perrin).

Those familiar with the film will revel in the way the chase across the Highland moors is staged (look out at this point, please, for the most specific homage to Hitchcock).

There were five curtain calls. There could well have been more, but I trust the actors went immediately to their resting areas to regain a bit of adrenalin.

The 39 Steps continues at the Playhouse until tomorrow. Box office: tel. 01865 305305 (www.oxfordplayhouse.com).