As we enter the intimate auditorium above The Hen and Chicken pub in Islington, raucous jazz music fills our ears. We are confronted with a simplistic set reminiscent of a stereotypical London hipster’s wine bar; a string of lanterns, rustic crates of wine and chalkboards adorned with kitsch quotations.

It’s the chosen location for “the meet up.” You know? That annual reunion that we all put ourselves through. Schmoozing and laughing with people from our past that we wish could stay there. This is the essence of Mum’s the Word, which – through the context of a schoolgirl’s reunion – captures the universal and unexplainable need to impress people we can’t stand.  But there’s more to it than that. Jess, Em, Heidi and Belinda have a dark, unspoken past that binds them together, and that they never speak of…until tonight.

With this “elephant in the room” haunting proceedings and eventually coming to light in a chilling climax, it feels unexpected to view Good One Theatre’s latest production as a comedy. Yet it is undeniable that Robert Hughes’ script highlights the humorous idiosyncrasies of the relationships we maintain with those we’ve known forever, yet don’t really know at all. The girls’ conversations range from politics to feminism until they finally settle on talking about each-other. It is in this scrutiny of each character that the true humour lies. The character of Em – although a self-proclaimed “bitch” – is particularly hilarious. Her domineering yuppie persona is perfectly performed by Emily Bairstow, and ideally befits the delivery of hilarious lines including “Macdonald’s is only fucking cheeky if you don’t have it every fucking day!”

We later learn that Em’s judgemental attitude and desire for social superiority lies at the heart of the group’s trouble past. “What is this troubled past?” I hear you ask – well, to reveal the nature of the girls’ predicament would be to spoil the play entirely. Hughes’ script meticulously feeds the audience nuggets of information about “the incident” throughout the play, keeping us intrigued until the climactic explanation. “We talked to the police, they said it wasn’t our fault” … “I’ve been writing to Zara” … “our Zara… why? I wish you hadn’t told me!” Each small reference to the secret event increases the tension and anticipation – who is Zara? What “wasn’t their fault”?

When we eventually find out the source of the tense atmosphere from an unwelcome stranger, we are slightly shocked. However, as the list of “atrocities” that this group of girls have committed continues, one becomes desensitized to the injustice, and wonders how this ending fits with the previously jovial atmosphere. The theatrical intention of these concluding moral lectures and foreboding promises of revenge is unclear; suggesting that the success of Mum’s the Word lies not in an attempt at revealing the solution to a serious mystery, but instead in its humorous observations of human behaviour and group dynamics.

Mum’s the Word is running at The Hen and Chicken’s Theatre until October 29.