Another gave the one-woman show three stars, commenting it “wasn’t a flawless piece of writing”, while others called it “contrived”, “wearisome” and “alienating”.
Now, six years on, her play is back for a sold out final revival and the widely-adored hit TV adaptation has amassed huge viewership figures, scores of award nominations and wins, including scooping the BAFTA for best female comedy performance.
Waller-Bridge is the woman of the moment. Her golden touch has seen her hired onto the latest James Bond as a writer and her series Killing Eve, a refreshingly original take on the spy genre, is preparing to enter its third series.
Her swansong performance as Fleabag has already garnered a host of five-star reviews, but whether audiences brought to the play from the fiercely loved TV version will agree is yet to be seen.
The eponymous tragicomedy centres around a wickedly funny, desperately sad, sexually unapologetic millennial woman living in London.
Despite cracking laughs all the way, it becomes clear she is riddled with a malignant guilt and her sexual liberalism has grown into a deeply unhealthy replacement for kind human interaction.
The play is set at job interview during which her thoughts reveal, among many, many other things, that she is mourning the death of her best friend, was dumped for masturbating while her boyfriend was asleep and that her guinea pig cafe is about to go under.
For all the pressure on Waller-Bridge, the opening night audience on Tuesday were clearly willing her to succeed. As the lights went down, whoops and cheers burst sporadically from the crowd – not very “theatre”, but it felt fitting.
If she is nervous, it’s hard to tell as Waller-Bridge conveniently begins the play frazzled and agitated as she runs in late to meet her prospective employer.
Lit by unflattering strip lights and perched on a chair in the middle of a small, beige lino floor with an even smaller patch of drab carpet, Waller-Bridge’s talent as a character actress is abundantly clear.
She shines in her physicality. She jumps headfirst into different characters as she regales you with the familiarity of a friend in the pub telling you their latest outrageous story.
In one scene, she plays Fleabag and Fleabag playing the protagonist’s sister. Though tiny gestures and articulated quirks, the audience doesn’t just see the sibling, but how Fleabag views her too.
Fleabag on TV became known for Waller-Bridge’s on-the-nose looks to camera, often with the viewer brought close to her face as she sliced through the fourth wall.
Waller-Bridge was able to amplify her knowing looks to reach the back rows of a West End Theatre without appearing to break sweat.
Her control over her body, facial expression and tone of voice sees Waller-Bridge one moment playing a dancing hamster to miming taking a series of incredibly explicit photos in a disabled toilet for an ex-boyfriend without breaking the audience’s sense of belief in the moment or giving them a chance to stop laughing.
For a piece where expectations are so high, it is impressive that the main let down was the often unnecessary and distracting sound effects.
It is also worth considering whether the whirlwind speed of the piece (which runs to just over an hour) would give new audiences enough time to get to grips with the complex character that is Fleabag in quite the same way that a two-series long TV show can. A lot is packed in.
For all the outrageousness of the piece, the expert crafting of Waller-Bridge and director Vicky Jones means that at no point does it cross into shock for shock’s sake – even when (no spoilers) one scene prompted repeated and loud gasps from the audience.
Although multitudes of fans will be left disappointed they were unable to get a ticket, Waller-Bridge, unlike Fleabag, knows when to leave her audience wanting more.
Fleabag is at Wyndham’s theatre, London, 20 August-14 September.