Cynthia doesn’t like going outside. She prefers the safety of her flat, and her dressing up box, and wigs, and lipstick, and she wants Maud to stop in with her. But Maud – twenty years her senior, supporting both of them – is beginning to suffocate inside Cynthia’s make believe world.

In Lipstick speaks to a long tradition of women-in-their-flat plays, from Pam Gems’ 70s feminist classic Dusa, Fish, Stas and Vi to the delicate depiction of a changing friendship in Chloë Moss’s This Wide Night. In the same model, In Lipstick gives us women safe inside the home they’ve made and a dangerous world out there, a world that has damaged them. But as the story develops, something strange and wild begins to emerge from inside this familiar architecture.

Unusually for a play about female friendship – or at least, for my emotional responses to these plays – the scenes between the two women are initially the less rewarding; there’s something about the sequences in which the two sing and dance or curl up on the couch, something that doesn’t quite ring true. When Maud (a subtle performance from Caroline Faber) escapes the confines of their flat for tentative dates with colleague Dennis (James Doherty), the play begins to come alive: suddenly the characters’ voices feel more real, and moments of pure invention and theatrical brilliance begin to bubble up.

At first, the heightened nature of Maud’s relationship to Cynthia (Alice Sykes) sits strangely beside the brutal naturalism of her dates with Dennis, whose studied gentleness and careful trivia-memorising gives way to hints of a past just as dark and complex as the women’s. But as In Lipstick progresses, you realise that feeling, that strangeness, is deliberate: Annie Jenkins has built a play of two discourses, the shared imagined world of the two friends and a completely naturalistic reality beyond. The final scene, in which the two are smashed together, is genuinely thrilling to watch. Jenkins keeps such a tight grip on her audience that you can barely believe this is her debut play.

Delyth Evans’ naturalistic design anchors us to reality, although the shaky revolve that takes us between Evans’ three sets provides undue tension: it’s a big technical shout for a fringe budget, and while it does always work, it sometimes sticks or slows. It’s a shame, because it occasionally detracts from the many things that work about the show – its three strong, confident performances, and Alice Hamilton’s inventive and careful direction – but only occasionally.

It’s a strong and surprising show, and Jenkins’s writing is the star. In its engagement with class politics, including a theatrically exciting sense of what is being performed, it is interesting and considered, but it’s the sheer bombastic weirdness of In Lipstick that will linger in the mind – at times impenetrable, at times bizarre, this is a memorable and entertaining debut play from a writer full of promise.

In Lipstick is on at The Pleasance until 27th January. More info here.