The Glasgow comedy festival earns its ‘international’ tag with a generous smattering of genuine intercontinental visitors in shows such as this intimate back-of-a-pub offering, which can’t have earned Maureen Langan much more than the cab fare from the airport, let alone her plane ticket from her native New York.

And he had to share the modest spoils with her opening act Rebecca Donohue, a compatriot who’s been living in Edinburgh for 18 months. A shrill, shrieky and sweary act, she’s 95 per cent attitude, five per cent actual content, thinking that if you bitch about something vigorously enough, it’s inherently funny.

She repeats the adjective ‘rapey’ with the gratuitous glee of someone who’s just heard it for the first time, thinks British people are polite (which might fly in the face of against Glasgow’s image, but she didn’t acknowledge the fact) and makes observations such as ‘Yorkshire pudding? That’s not a pudding.’ She got laughs, but I found her more grating than funny.

Headliner Langan’s sass was of a more pointed kind; less aggressive but more caustic, coming from a genuine sense of bitterness at how screwed up society has become.

The daughter of a Bronx garbage collector, she was brought up to believe that talent and hard work would get you places. But her university education and years of experience as broadcast journalist count for nothing in the media that prizes the cosmetic above the competent. So she’s understandably resentful that newspaper columns are given to hookers who gain notoriety from political sex scandals, not intelligent middle-aged women such as her.

Bitterness is a useful comic tool, though, and Langan wields it with skill and precision. ‘I feel like Canada,’ she gripes. ‘I’ve got so much to offer, but nobody gives a shit.’

Her time in front of the camera has given her a poise and confidence on stage, and she shares her tart, opinionated views with wry charisma. She does occasionally slip into the crass, with her routine about how old men get laid but old women don’t featuring a few hacky Stephen Hawking jokes as well as the very unfortunate line ‘he discovers black holes – and I don’t mean African American vaginas’, but this is definitely atypical of her otherwise smartly piercing wit.

This is a consistent, well-constructed 45-minutes of elegantly feisty stand-up, which will surely secure Langan much bigger venues than this in the return visits she'd be more than welcome to make.