Drama Theatre, Sydney Opera House, April 15.

“I never realise how dead I am until I meet people like you,” says the rather correct “diplomatist” Richard Greatham (Alan Dukes) to the chatelaine of the unorthodox country house to which he’s been invited for the weekend. Call it the Bliss factor, a tornado-like life force that sweeps up everyone in its path. At least it does in Sydney Theatre Company’s exhilarating new production of Hay Fever, which director Imara Savage gives an intense, sexy energy that blows away the cobwebs so often clinging to Coward and his 1925 comedy of bad manners.

At the centre of the whirlwind is Judith Bliss (sublime Heather Mitchell), an actress who is nominally retired but has simply transferred her theatrics to a more intimate setting. As we soon discover, each member of the Bliss family has asked a friend to stay without telling the others. They are not natural hosts and are wildly self-dramatising. There will be complications, not the least of which is who will get to stay in the Japanese room.

Richard’s confession to Judith is the key to this work. Hay Fever celebrates those people in the world who burn more brightly than others because they have fewer limits. They are the sun and we are bits of space junk caught gratefully in their orbit, at least for a while.

When Coward wrote Hay Fever, World War I just a handful of years in the past and the Edwardian era was over. Time to have some fun. Coward was only 24 at the time but had been moving in artistic circles for more than a decade – he was a professional actor from the age of 11 and wrote his first West End play at 20. His family was not well off and Coward was entirely self-made. It’s tempting to think that the get-the-guest antics of the Blisses were inspired not only by Coward’s acquaintance with American actress Laurette Taylor and her games-playing family, but were also a reaction to the days in which his mother had to take in lodgers to make some money.

Coward claimed to have written Hay Fever in three days without revision and there’s no reason to doubt him. That’s not a criticism – he wrote Private Lives in “roughly” four days, by his account – but it does remind us not to get too profound about the piece. Indeed, the superficiality is the point of it and Savage – with one caveat – astutely finds the right tone for today’s audience. Her production is invigoratingly untethered from the 1920s, picking up on the contemporary adoration of self while being not in the slightest bit condemnatory.

The daughter of the family, Sorel (Harriet Dyer), indulges in one or two little shows of conscience, voicing the belief that everyone in the family should behave rather better, but her desire to be a nicer, finer person is more pleasing concept than possibility. Nor should it be. Sorel, played by Dyer with a mixture of whiny childishness and acute perceptiveness, is clever enough to know that “the people we like put up with it because they like us”. It’s an unvirtuous circle. When this lot of guests have gone there will be other willing victims.

Sorel’s brother Simon (Tom Conroy) and she have no visible occupation and still live at home with Judith and their father, David (Tony Llewellyn-Jones), who writes very bad novels and is not dead, as Judith’s slightly dim young guest and admirer Sandy Tyrell (Josh McConville) had surmised. David is, in fact, in the house and has invited the naive Jackie Coryton (Briallen Clarke) to the country so he might study her as “a useful type”. That Sorel’s guest is the very Richard who is enchanted by Judith hints at the roundelay that develops, one in which Simon’s sophisticated guest Myra Arundel (Helen Thomson) will be discovered by Judith in a compromising position with David. He is lying on top of Myra on the floor.

The teasing Is endless and wickedly manipulative and the guests don’t stand a chance. Nor does the audience really. As Savage showed with last year’s After Dinner, an early comedy by Andrew Bovell (also at STC), she has a great eye for physical comedy and a superb cast to enact it. Richard, for example, gets two of the best sight gags in the show – beautifully played by Dukes – and they give the mature diplomat warmth and colour. Conroy’s Simon plays up his bohemian credentials by drinking wine at breakfast and professing violent love for women despite exuding an air of being not particularly interested in them. Judith is one of the great comic roles in 20^th century theatre and Mitchell makes her every whim, tic and idiosyncracy adorable (bar one, but that’s the caveat I’m coming to and it’s not her fault). Mitchell’s pre-Raphaelite beauty is intoxicating, as is her way with a seductive phrase. “I’ve been pruning the calceolarias,” she throatily purrs to Sandy. It’s an invitation to unimagined delights that seduce us all.

In what is perhaps the trickiest role to pull off in this updating, Genevieve Lemon plays Judith’s housekeeper (and former dresser) Clara in the manner of a beloved, eccentric retainer in a conventional British farce. It’s wacky, no doubt about it, but fits in with the idea of theatricality not only as an attribute of the Bliss family but as a style of performance.

The idea of life as an act is gorgeously reinforced by designer Alicia Clements’s divinely ramshackle conservatory, the centrepiece of which is a claw-foot bath that doubles as a sofa, and the lurid curtains that frame the stage and close at a majestic pace. The boldest example is the inclusion of Amy Winehouse’s Back to Black, lip-synched by Judith in lieu of a lovely little song at the piano. It is a surreal, provocative choice although not necessarily out of keeping with Judith’s mercurial temperament. Less successful – this is the caveat – is Savage’s decision to replace the names of British newspapers with those of Sydney ones. Judith is proposing a return to the stage and speaks of the thrill of a first night, the critics “all leaning forward with flowing faces, receptive and exultant …” Savage has Mitchell address the audience directly here and, just for a moment, the bubble that encloses these characters bursts. The Winehouse song – just – stays inside that bubble.

That seemed to me a misstep in a production where artificiality is so prized. Savage’s brilliant ending says it all. The climactic touch is a halo of light that envelops the Bliss family, accompanied by a lush, golden-days-of-Hollywood swelling of strings. (Trent Suidgeest is responsible for the lighting; Max Lyandvert for sound design and music.) The guests have slipped away and the Blisses are now at their most relaxed and content, a family very much at peace, albeit noisily, with one another in their own little world.

Hay Fever ends on May 21.