Revelations, Hampstead Theatre, London

"We don't hold truck wi' that Seventies wife-swapping," says Jimmy in Stephen Lowe's play Revelations. He's arrived for an internet-arranged orgy and announces that he and his wife want everything to go on in one room, none of that "bunk off to separate bedrooms ballocks". But the action - or lack of it - in the play is Seventies through and through. Except for the role that technology plays, we could be watching a drama from that decade when the youthful and artistic hedonism of the Sixties went mass market. The couples who have got together ostensibly for physical satisfaction are really using sex, you see, to avoid or conquer their sexual and emotional problems. But this point, obvious within two minutes of their appearance, is hammered home for more than two hours. I was, sadly, alone in loathing Abigail's Party, that dull, mean-spirited play, but I think I will have some company in my opinion of this even duller and far more pretentious one.

Anthony Clark's plodding pace exposes Lowe's self-indulgent and false conceits to the full. The host, Edward (Michael Elwyn) is a big bug in academic Pre-Raphaelite circles. Though his choppy, breathless talk moves quickly from art to sexy art to sex, Edward is not one of those profs who end their tutorial with a pounce. As aloof from his female students as he is from his wife, he is pompous, humourless, defensive, and irritable. Which makes it highly unlikely, to say the least, that he would have invited Jimmy - the "ee-bah-goom" swinger who rapidly gets Edward's back up - to the orgy. Not only is Jimmy chirpily ignorant, he is an old hand at wife-swapping, and arrives with boxes of equipment, advising that it's best to be prepared and ordering Edward about. Jimmy's wife, though (adorable Hetty Baynes, who arrives looking like a little Red Riding Hood who has eaten the wolf) is a great asset to any sex party, ready in convent headgear to enact (the play's one good joke), "The Blue Nun's Story."

The youngest couple, Jack and Jill, take us back to the Seventies with their resemblance to the stars of The Good Life, especially Bertie Carvel's twinkly Jack, who repeatedly ducks his curly head to his chest and chuckles amiably. Julia Swift gives a realistic and even touching performance as Edward's attractive, wistful wife, a woman who has become desperate to improve her marriage - or, if that can't be saved, her own life. The unlikeliness of the situation rises sharply toward the end, with Edward rumbling approvingly ("Eros, Thanatos - powerful themes"). With most such plays, the serious stuff seems to be tacked on to provide a justification for the rumpy-pumpy, but in Revelations, as Jack and Jill act out Eve and Adam roles upstage, the sex seems compensation for having to endure this orgy of narcissism.

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