Now, while Coward and cocktails go together like prunes and custard, Coward and the human vagina are not so regularly associated. Indeed, even though Design for Living famously focuses on a threesome who end up, after various pairings, in a menage a trois, the atmosphere of a standard production is dismayingly, evasively neuter rather than charged with genuine erotic ambiguity.
You realise how thoroughly Mathias means to change this from the opening moments when, wrapped only in a makeshift sarong and to a sultry soundtrack, Rachel Weisz's devastatingly sexy Gilda emerges from her bedroom into the dark, tousled Paris studio. Cocking her bare leg on the fridge, she sensuously strokes it and then basks, in a manner that's both arousing and delightfully ridiculous, in the fridge's electric glare. It's a safe bet she has not left an empty bed.
Rather as Philip Prowse's 1989 production of The Vortex played for real the drug fixes and mother-fixation in Coward's first big success, so Mathias makes sure that the carnal compulsion that keeps drawing this trio together does not get sublimated or euphemised as just a shared ritzier-than-thou chic. He also keeps it funny. The raw, wrenched emotions that are on display are given a further boost of immediacy by the fact that the production's look has one foot in the Thirties and one in the present, the men's clothes sometimes suggesting no great gap from Gap. Clive Owen and Paul Rhys as the men speak in, respectively, a flat Midlands accent and a Welsh-tinged one. Without under-selling the wit, the rhythm of the lines has been refreshingly loosened up from the usual effete telegraphese.
It's a very funny as well as sexy account of the play. As the disapproving housekeeper, Johanna Kirby makes some hilarious interventions, including a splendid unscripted foray with a vacuum cleaner across the charmingly played drunk-scene that turns into mutual seduction between the two men. The New York episode, where the male pair are metamorphosed into a top-hat-and-tails double act, all smirks and mascara as they shock the rich Philistines, here deliriously knocks the lid off a straight couple's clearly neurosis-ridden marriage. Mathias ensures you feel sorry for Gilda's marginalised husband, Ernest - mocked, as he exits, in mad parrot-house fashion by the menage. But he also lets you feel the potent seductiveness of the threesome in a production that would have brought out the bisexual in Noel Coward.
'Design for Living' is at the Donmar Warehouse, London WC2, until 5 Nov (Booking: 071-867 1150)