Fairly regularly a play turns up - the Blue Room, The Graduate - that makes London theatre sexy. Glengarry Glen Ross may be the first to make it butch. The night I saw James Macdonald's revival of this Mamet drama depicting aggressive betrayal in a real-estate sales office, the audience was full of young men. Great, hooting, big-shouldered groups of them. They hung around by the entrance, smoking furiously. They bulldozed their way to their seats. They bellowed with laughter at the crude racial stereotypes and cruder abuse ("f** you, you stupid c***") Mamet's characters spray at one another.

During the interval they grabbed fistfuls of overpriced beer bottles and chugged them down. When I struggled back to my wife, she said a couple of them had cupped her waist to steer her out of their path. "They weren't copping a feel," she said. "They were just overdosing on testosterone."

In a way, it was refreshing. Most theatre audiences are middle-aged to elderly and most tickets are bought by women. I don't think the strapping lads I shared the stalls with were dispatched by their mums or girlfriends for this theatrical night with the boys. I don't think they were lured by the firecracker performance of Aidan Gillen, or Jonathan Pryce's portrait of slow implosion. I think they were there to get off on the words of a writer routinely described as "muscular".

Which is fine, except that Mamet's bicep-flexing machismo is firmly rooted in failure. Glengarry's salesmen have terrible jobs and worse lives. Their bravado is a smokescreen. They are surely all divorced. The most telling lines are the three, inconclusive references that Pryce's beaten-down Shelley Levene makes to "my daughter ...". Whether she's his talisman or his cross to bear we don't know, but this offstage female presence is the only thing that stops him despairing and keeps him working. And we know, or we should know, that Gillen's flashily furious Ricky Roma will turn into Shelley one day.

Maybe the lads appreciated this and just got off on the syncopated masculinity of Mamet's undeniably funny dialogue. Maybe they are laughing at, not with, themselves. And maybe it's a heartening trend. With Steven Berkoff 's hypermale On the Waterfront due in the West End next year, groups of young males will sit around to debate the evening ahead thus: "Pub? Kickabout? Play?"

• Booking until 12 January at the Apollo Theatre (0871 733 1000).