‘If this is a love story, you can wear whatever pants you want’.

The stage is strewn with tins and boxes. Containers to put things in. Two performers, Rachel Mars and nat tarrab, stand before the audience in matching white vests and baggy jeans. Autobiographical in its origins this is a piece, not just about growing up as a tom boy – though of course that’s a large part of it -but more broadly about the frustration that comes from social labelling, from being wedged into slots where you just don’t fit.

In ways both playful and engaging, Mars and tarrab explore gender and identity, cramming in cod scientific lectures on life’s tendency to disappointment and advice on how to survive those disappointments when they come (by adopting a kind of psychological brace position).  These disappointments can take many forms: Hollywood is not to be trusted; movies lie to you and lovers leave.

Even when covering familiar ground – there is some vigorous cunt-reclaiming in the manner of Eve Ensler’s Vagina Monologues– the piece is entertaining and thought provoking. Where it asks do all those tom boys go? What happens when they cross the line from adolescence and adulthood? Does the frustration simply dissipate or do they learn to be more ‘female’ because it’s the easier path?

As performers, Mars and tarrab have a strong rapport both with each other and the audience. There are physical sequences during which they move in unison and, in a recurring motif, they appear to be trying to brush something off, shed something unwanted. These are interspersed with autobiographical snippets: the childhood trauma of the hated pink party dress, the coveted and beloved Spiderman trainers, the pleasures of tree-climbing and the satisfying tearing of taffeta. Naked Barbie dolls, with their alarming plastic pubic areas, are waggled with distaste; pink knickers are strung from a clothes line.

The piece is light-footed and witty, and the sense of exasperation at the narrowness of gender labels is frequently cut with humour. It is however at its most intriguing and uncomfortable as a piece when it acknowledges that there are uglier, nastier things than being asked, for the umpteenth time, if you’re in the right toilet; that to step across those well-defined gender lines is an act not without risk.

Tom Boy Blues also interrogates the tendency of marginalised groups to police their own borders, as demonstrated by the moment when tarrab turns to Mars, with her slighter frame and wavy dark hair, and menacingly suggests she’s not quite enough of a tom boy. Yet more containers; more boxes to tick and fill.

The piece utilises some familiar devices and imagery but it’s done with warmth and a nostalgic appeal – which, admittedly, will be particularly acute if your ten-year-old self was permanently dungaree clad and had a fixation with Lego. And while this terrain may have been covered before, gender identity is a fluid thing and the boundaries have, if anything, been narrowing, so their voices on this matter are both welcome and resonant.