I don't want to tread on anyone's sensibilities here, but sex really can be quite absurd in both its psychological and physical manifestations. For my principal witness, I call Dead Funny, Terry Johnston's West End hit of 1994 in the Rough Magic production now at the Project. It might be described as a serious farce, so it covers the ground fairly comprehensively.

As it opens, Richard (James Wallace), a mid-thirtyish obstetrician, and his wife Eleanor (Kate O'Toole) are having trouble with their sex life, and are trying to follow a series of counsellor-prescribed steps to get it going again. He hates it, but she is determined, so he reluctantly strips so that she may touch his body at will. Their strained foreplay is exquisitely embarrassing, and ends in a good gag that startles one into convulsed laughter.

Enter Brian (Mal Whyte), and the main comedy-stream begins. He brings the shocking news that comedian Benny Hill has died, and it emerges that he and Richard are leading lights in the Dead Funny Club, for whom Benny was an icon. A kind of English wake is planned so that the deceased may be appropriately mourned. Fellow members Nick (Miche Doherty) and his buxom wife (Janet Moran) arrive, and plots thicken.

Two dramatic streams come into confluence. Sex send-up jokes take the high ground, and the private pain of the characters - they are all hurting with repressions or betrayals - bubbles uneasily beneath. The jokes mix hilarity and vulgarity in equal measure, mostly rib-ticklers, and the probes show real people in serious difficulties with their lives. But the two don't always mix well, and it is the serious side that is finally diluted.

So this one is really for adult laughs, and does not disappoint on that score. Mal Whyte is quite brilliant throughout, and Kate O'Toole cuts through the comedy to be a convincing figure surrounded by near-grotesques. James Wallace has an engagingly easy style, and Miche Doherty with Janet Moran do nicely as another married couple biting on bullets.

Director Lynne Parker conducts it all, from pie-in-the face action to emotional standoff, with authority, although the dying fall of the ending is something of a prolonged squelch. It would have been nice to leave laughing.

Runs to May 26th.Booking: 1850-260027