If this play wasn't in Welsh, viewers could be forgiven for guessing that it had been written by Jonathan Harvey.
For around 1¾ hours, we witness four gay men cruising around Cardiff in search of fun but more likely to find heartache.
The protagonist is Aneurin, now resident in London. He is a writer who appears to be in denial, though you have to wait until the closing moments to discover what is being denied.
Simon Watts's character has teamed up with his old flame, Paul Grehan as the rather insultingly, if affectionately, nicknamed Dada, who is 20 years older than his friends.
The group is completed by the seemingly ill-matched couple of schoolteacher Rhys and his hunky partner Gareth, respectively played by Paul Morgans and Michael Humphreys.
After some high jinx at home, the lads go clubbing and thanks in part to significant quantities of drugs, trouble follows them through what becomes a rather melodramatic night.
The first of two main flare-ups results when Gareth meets old rugby friends from his straight days. The second appears in the shape of Gavin. Joshua Price is the underage pupil of Rhys who is sexually inquisitive and first picks up Dada and then goes home with Aneurin.
The ensuing ructions take campness to a new peak and, at one point, it seems that the old friendships will never recover.
The final scenes give the play greater depth and suggest that Aneurin may not be as shameless as he would like us to believe.
Llwyth is an unusual choice for the Sherman to bring up to Edinburgh, given that many of the in-jokes are about Welsh celebrities unknown outside the Principality. Further, in a wordy play, most of the speech is in Welsh, requiring viewers to concentrate hard on the excellent surtitles rather than the stage for the majority of the time.